India and Pakistan have blamed each other for escalating tensions as the US and others countries urge both sides to de-escalate
On Thursday, India's army accused Pakistan of launching drones and missiles on three military bases in India and Indian-administered Kashmir, which Islamabad denies
Pakistan said earlier it had shot down 25 Indian drones - India has not commented
Pakistan says 31 people have been killed and 57 injured by air strikes in Pakistan and Pakistan-administered Kashmir, and firing along the Line of Control, since Wednesday morning
Meanwhile, India's army says at least 16 civilians were killed by Pakistani shelling on its side of the de facto border
India says the initial missile strikes were a response to a deadly militant attack on Indian tourists in Pahalgam last month - Islamabad denies involvement
Indian-administered Kashmir has seen a decades-long insurgency which has claimed thousands of lives. India and Pakistan both claim Kashmir in full
Watch: How tensions escalated between India and Pakistan
The Indian embassy in Washington, DC says that National Security Adviser Ajit Doval spoke with US Secretary of State Marco Rubio - who is also currently serving as acting national security adviser at the White House - after the strikes
Doval "briefed him on the actions taken", the statement posted on X says.
Smoke seen rising over Kotli in Pakistan-administered Kashmir
Footage verified by the BBC from Kotli in Pakistan-administered Kashmir shows smoke billowing in the distance.
Earlier, Pakistani military spokesperson Ahmed Sharif said two civilians had been killed in a strike there.
Anbarasan Ethirajan
South Asia editor, BBC World Service
Image source, ReutersA view of Muzaffarabad - in Pakistan-administrated Kashmir - during a blackout
It’s a dramatic escalation between the two nuclear-armed rivals.
Even though there were expectations that India could launch some sort of military action, the intensity of the missile attacks inside Pakistan had surprised many.
India says that some of the places it was bombing were linked to militants, and they were not targeting Pakistani military sites.
Pakistan has vowed retaliation, and the nature and targets of this will determine Delhi’s counter-reaction.
Both countries think they can manage escalation, but tensions are running high and it’s difficult to predict the course of any military conflict.
In the past the US and other countries intervened to rein them in.
With the Trump administration’s focus diverted due to other global issues, it remains to be seen how quickly Washington will step in to de-escalate.
Political leaders in both countries will want to show their public that they have acted decisively and claim victory.
They have taken a huge gamble.
More now from Pakistan military spokesperson Lt Gen Ahmed Sharif Chaudhry, who is speaking to our colleagues on the BBC News channel.
He says the military has shot down at least two Indian jets and a drone.
Sharif says Pakistani forces are on the ground but refuses to specify where.
He says Pakistan has a right to defend itself and that defence is currently under way.
The Reuters news agency meanwhile is quoting Pakistan's defence minister as making the same claim that Indian planes have been shot down.
There has been no comment on this claim from India and the BBC is unable to independently verify it.
Seven people have died including at least two children, Lt Gen Ahmed Sharif Chaudhry, a spokesperson for the Pakistani military, tells the BBC.
Sharif says the strikes hit multiple locations including a mosque.
"This is flagrant violation of international law," he says.
Image source, ReutersPakistan's Prime Minister Shehbaz Sharif has just issued a statement,.
He says: "The treacherous enemy has launched a cowardly attack on five locations within Pakistan. This heinous act of aggression will not go unpunished.
"Pakistan reserves the absolute right to respond decisively to this unprovoked Indian attack — a resolute response is already underway.
"The entire nation stands united behind its armed forces, and our morale and resolve remain unshaken. Our thoughts and prayers are with the brave officers and soldiers of Pakistan.
"The people of Pakistan and its forces are fully prepared to confront and defeat any threat with our strength and determination.
"The enemy will never be allowed to achieve its malicious aims."
Image source, EPAA spokesperson for United Nations Secretary-General Antonio Guterres says he is "very concerned about the Indian military operations across the Line of Control and international border".
Stéphane Dujarric adds: "He calls for maximum military restraint from both countries. The world cannot afford a military confrontation between India and Pakistan."
Farhat Javed
Reporting from Islamabad
Large explosions were heard earlier in Muzaffarabad in Pakistan-administered Kashmir - and locals have been telling the BBC what they experienced.
"I was fast asleep when the first blast shook my home," says Mohammed Waheed, a resident living adjacent to the Bilal Mosque, which was reportedly one of the sites hit.
"I rushed out into the streets, where I saw others doing the same. Before we could even process what was happening, more missiles struck, causing widespread panic and chaos."
Waheed says dozens of people were injured and they were being taken to a hospital about 25km (16 miles) away.
"Children are crying, women are running around, trying to find safety. We're terrified, and we don't know what to do. People are fleeing their homes, and the sense of uncertainty is overwhelming."
He says security forces were at the scene but he could not understand why a mosque had been targeted.
"It was a normal street mosque where we prayed five times a day. We never saw any suspicious activity around it."
Shafat Farooq
Reporting from Srinagar, Indian-administered Kashmir
Earlier, the Indian army said Pakistan had fired artillery into India-administered Kashmir in the area of Bhimber Gali.
Locals tell me they have heard explosions in several parts of Indian-administered Kashmir, including Mendhar which is near Bhimber Gali.
Where I am based, in the city of Srinagar in Indian-administered Kashmir, there’s heavy fighter jet activity overhead.
This is a fast developing story. Stay with us for further updates.
Asked about the Indian strikes, US President Donald Trump replies: "It’s a shame."
Speaking at the White House in Washington DC, he says that "we just heard about it just as we were walking in the doors of the Oval [Office]".
"I just hope it ends very quickly," Trump adds.
Trump: I hope it 'ends very quickly'
Two civilians in Kotli, in Pakistan-administered Kashmir, and a child in Bahawalpur, Pakistan, have been killed in India's strikes, a spokesperson for Pakistan's military says.
Lt Gen Ahmed Sharif Chaudhry adds that 12 more civilians were injured in Ahmedpur Sharqia in Bahawalpur, according to reports from Pakistani media Geo News.
He also says a family including a child have been trapped under the rubble of a collapsed house.
India’s strikes come in retaliation to a militant attack that killed at least 26 people, mostly tourists, in the picturesque resort town of Pahalgam in Indian-administered Kashmir on 22 April.
Militants opened fire on people who were visiting Baisaran, a mountain-top meadow three miles (5 km) from Pahalgam.
Some survivors of the attack said that Hindu men were specifically targeted by the gunmen.
Pakistan has denied involvement in the attacks, but Indian police say two of the four militants they suspect for the attack were Pakistani citizens. A manhunt by the security forces is still under way.
Both India and Pakistan have announced a range of retaliatory measures against one another including closing borders and suspending a river water sharing treaty. Troops from both sides have also traded small arms fire.
Indian prime minister Narendra Modi had earlier said the country will pursue the perpetrators of the attacks “to the ends of the Earth”.
Pakistan's Defence Minister Khawaja Asif has been speaking to Geo TV.
He says that India launched missiles at Pakistan from within its own airspace.
He goes on to say that the strikes hit civilian areas. India's claim of "targeting terrorist camps" is false, he says.
The BBC has not yet been able to independently verify the locations struck.
The Indian army says Pakistan has "fired artillery in Bhimber Gali in Poonch-Rajauri area" in India-administered Kashmir, just across the dividing lines.
India's armed forces are "responding appropriately in a calibrated manner," the army says in a post on X.
The director general of Pakistan's military public relations wing, Inter-Service Public Relations (ISPR), tells Pakistan news channel Geo TV three locations have been hit by Indian missiles.
Lt Gen Ahmed Sharif Chaudhry says they are Muzaffarabad and Kotli in Pakistan-administered Kashmir, and Bahawalpur.
This is the moment audio captured explosions heard in Pakistan-administered Kashmir, near the city of Muzaffarabad.
Reuters is also reporting multiple loud explosions in several places in Pakistan and Pakistan-administered Kashmir.
The news agency is quoting witnesses as saying that power was blacked out in Muzaffarabad.
The Indian government says its forces have launched "Operation Sindoor", "hitting terrorist infrastructure" in Pakistan and Pakistan-administered Kashmir "from where terrorist attacks against India have been planned and directed".
In a statement, the Indian government says "nine sites have been targeted".
"Our actions have been focused, measured and non-escalatory in nature. No Pakistani military facilities have been targeted. India has demonstrated considerable restraint in selection of targets and method of execution."
The statement adds that the attack was ordered after last month's deadly militant attack on tourists in India-administered Kashmir.
A spokesperson for Pakistan's military says Islamabad "will respond to this [attack] at a time and place of its choosing".
"All of our air force jets are airborne. This is a shameful and cowardly attack that was carried our from within India's airspace," the spokesman adds.