The US assassination of top Iranian general Qasem Soleimani happened barely 24 hours ago, but the reaction is still flying thick and fast.

Iran has vowed retaliation, but so far there is no indication of what form that might take.

President Trump said the strike was carried out to "stop a war, not to start a war" and that Iran was planning an imminent attack on the US.

Follow all the latest updates in our main news story:

• Iran vows 'severe revenge' for top general's death

And for more BBC analysis, start here:

• WATCH: Who was Iran's 'rock star' general
• Does Trump have a strategy?
• How strong is Iran's military?
• The response options open to Iran

Trump's decision to authorise an air strike that killed Iran's most powerful military commander has seen tensions between the two nations escalate.

In this analysis, experts debate what Trump's strategy may be:

Qasem Soleimani killed: Does Trump have a strategy?

So many Americans are afraid of being drafted to fight a war against Iran that they have crashed the website of the US Selective Service - the defence department agency that tracks information about American men who are eligible for military enlistment.

Americans are keen for more information about the draft age, exemptions and other requirements.

The draft was eliminated during the Vietnam war in 1973, but American men aged 18-25 are still required to register in case a draft ever becomes necessary.

But, as the Selective Service advised, Congress and the president would need to pass formal legislation to institute the draft again.

Some of President Trump's critics have questioned the wisdom of targeting Qasem Soleimani, but many people in the region are grateful for Soleimani's death.

Writing for The Atlantic magazine, external, former BBC correspondent Kim Ghattas in Beirut notes that in parts of Syria - where the government has been backed by Iran - some people are passing around trays of sweets in celebration.

"Soleimani was so central to almost every regional event in the past two decades that even people who hate him can’t believe he could die," she writes.

Image source, Getty Images

The Pentagon's top general has told reporters that the US had "clear and unambiguous" intelligence that Iran was planning a "campaign of violence" against Americans.

According to the Washington Post, external, Chairman of the Joint Chiefs of Staff Mark Milley warned that the attacks "might still happen".

He said that the danger of taking no action against Soleimani was higher than choosing to strike.

"Is there risk? Damn right there’s risk," he said about possible retaliation. "But we’re mitigating, and we think we’re taking appropriate mitigations."

Image source, Getty Images

The Mayor of New York City, Democrat Bill de Blasio, has held a news conference to warn city residents they are "now potentially facing a threat that’s different and greater than anything we have faced previously".

Previous attacks in the city have come from non-state actors, he noted, adding that "as of last night, we are dealing with a different reality".

He adds that "at this point" there is a "de facto state of war between the United States of America and Iran".

Other cities, including Los Angeles, Washington DC and Miami have also announced a heightened security threat.

The EU's Foreign Minister Josep Borrell warns that the cycle of violence in Iraq must end before it "spirals out of control".

"Another crisis risks jeopardising years of efforts to stabilise Iraq," he said in a new statement.

"Furthermore, the ongoing escalation threatens the whole region, which has suffered immensely and whose populations deserve life in peace."

Trump's brief news conference is now over.

The president began the press conference by threatening the enemies of America.

"We will find you. We will eliminate you. We will always protect American service members," Trump says.

Gen Qasem Soleimani "made the deaths of innocent people his sick passion", he says, and adds that the attacks affected people "as far away as New Delhi and London".

"We can take comfort knowing that his reign of terror is over," Trump says, adding that he made the decision to kill him to "stop a war".

"We do not take action to start a war," he added.

"I am ready and prepared to take whatever action is necessary. And that particularly refers to Iran," he continues.

The US president describes Gen Soleimani as a "terrorist" who was "responsible for the deaths of hundreds of American" civilians and soldiers.

Image source, Getty Images

From the CIA-orchestrated overthrow of Iran's prime minister in 1953, to tension and confrontation under Trump, here's a look back over more than 65 years of tense relations between Iran and the US.

US-Iran relations: A brief history

Iranian Foreign Minister Mohammad Javad Zarif has been speaking in Dubai, telling state TV that the US airstrike "was clearly a terrorist action".

"Iran will launch various legal measures at the international level to hold America to account for Soleimani's assassination," Mr Zarif said, according to Reuters news agency.

Earlier, in a tweet sent soon after the strike, Mr Zarif accused the US of "international terrorism".

Image source, Getty Images

Defence companies have seen their stock prices rise in the wake of the targeted airstrike in Baghdad - leading some to accuse them of being "war profiteers".

Lockheed Martin, Northrop Grumman, General Dynamics and Raytheon all saw a boost in early market trading.

But defence companies weren't alone. Gold and Bitcoin have also climbed in today's trading.

Trump will be holding a rally in Miami in less than three hours, where he will be debuting the "Evangelicals for Trump" coalition.

The event was first announced one day after evangelical magazine Christianity Today published a scathing editorial advocating for Trump to be removed from office.

The speech, which is expected to take the form of one of Trump's signature political rallies, comes amid Trump's two-week holiday at his Mar-a-Lago resort in Palm Beach, Florida.

It's not known whether Trump will directly address the US airstrike that killed Soleimani, but according to CNN, he will "likely address" the news.

Image source, AFP

Democratic presidential candidate Bernie Sanders began a campaign event in Iowa decrying the "assassination" of Soleimani, saying "this could lead to even more death, even more conflict, even more displacement in that area of the world".

Trump, he says "listened to right wing extremists" and ignored the advice of his own security advisers.

Speaking in New Hampshire, his rival Pete Buttigieg, a military veteran of the Iraq war, asked "what are the repercussions of decisions like this?"

"This is not a game. This is going to have consequences, and having served overseas, I know the real life consequences that we could face, especially if this is going to lead to a war."

Tulsi Gabbard, another military veteran vying for the Democratic nomination, tweeted a video calling Trump's actions "an act of war" that has "put us in a state of war with Iran... pushing us deeper into an endless quagmire".

The Hawaii congresswoman drew condemnation in Washington in 2017 when she travelled to Syria to meet President Bashar al-Assad.

Image source, Getty Images

US Homeland Security Acting Secretary Chad Wolf has released a statement praising the air strike against Soleimani and assuring Americans that the agency "remains vigilant and stands ready, as always, to defend the Homeland".

His statement notes that "there are currently no specific, credible threats against our homeland".

Wolf added that senior Homeland Security officials convened "last night and earlier this morning to assess potential new threats and component actions to respond to the constantly evolving threat landscape".

Image source, PA Images

Richard Ratcliffe says he is worried about what the killing of Gen Qasem Soleimani will mean for his wife, British-Iranian woman Nazanin Zaghari-Ratcliffe.

Mrs Zaghari-Ratcliffe was arrested and imprisoned three-and-a-half years ago on spying charges, which she denies.

Image source, PA Images

Mr Ratcliffe says increasing tensions have always been bad for his wife's case.

"There's probably a concern, at a selfish level, as to what this means for Nazanin's case, and the fact that tensions increasing is always bad for a solution and someone being released," he says.

"There's always a worry that things could get worse. And then, for my in-laws sitting in their front room in Tehran, just worrying... is this going to mean that we are stepping closer to military action."

The US Department of Defense is preparing to deploy more troops to Kuwait following the attack on Soleimani.

Unnamed US officials tell US media that about 3,500 troops will be sent from the 82nd Airborne Division based at Fort Bragg, North Carolina.

WXII-News, external in Winston Salem, North Carolina, reports that the full Immediate Response Force brigade - about 4,000 soldiers strong - currently stands ready to deploy.

On Wednesday, more than 650 paratroopers from the base were sent to the Middle East after an attack on the US embassy in Baghdad.

Iran has vowed "harsh vengeance" on the US for killing its most powerful military commander, General Qasem Soleimani.

But what do we know about Iran's military capabilities?

Find out here

Image source, Getty Images

Senate Majority Leader Mitch McConnell has spoken in support of the strikes in Baghdad.

"This morning, Iran's master terrorist is dead," the senior Republican said.

"The architect and chief engineer for the world's most active state sponsor of terrorism has been removed from the battlefield at the hand of the US military.

"No man alive was more directly responsible for the deaths of more American service members than Qasem Soleimani."

Image source, Reuters

But Democratic Senator and Minority Leader Chuck Schumer said the "gang of eight" - those leaders within Congress who are usually briefed on classified matters in advance - had not been briefed on the air strikes.

He said President Donald Trump would need congressional approval for further long-term action on Iran.

"It is my view that the president does not have the authority for a war with Iran," he says.