Bangladesh deputy opposition leader arrested in Dhaka

Mr Alamgir was arrested after trying to leave the press club, where he said he was forced to stay on Monday night after it was surrounded by pro-government supporters

Police in Bangladesh have arrested the deputy leader of the main opposition party, as tensions rise over its calls for nationwide protests and blockades.

Bangladesh Nationalist Party (BNP) Secretary General Mirza Fakhrul Islam Alamgir is being held on charges of arson, bombings and vandalism.

His arrest comes as opposition leader Khaleda Zia was confined by police to her offices for a fourth day.

The unrest comes on the first anniversary of disputed elections.

The vote - boycotted by the opposition who said it would be rigged - was won by the ruling Awami League.

'Vast prison'

Mr Alamgir was arrested as he tried to leave the National Press Club in Dhaka, where he said he was forced to stay overnight on Monday after it had been surrounded by pro-government supporters.

Witnesses say that his car was commandeered by police officers who drove it to their headquarters.

Opposition supporters set fire to vehicles in Dhaka on Tuesday

Khaleda Zia has been confined by police and government supporters to her offices since Saturday

Speaking just before his arrest he warned that Prime Minister Sheikh Hasina's government was turning the country into a "vast prison".

He repeated calls for the opposition to enforce a nationwide transport blockade.

The government for its part has warned that Ms Zia could face murder charges over an arson attack it says was carried out by BNP supporters which left three people fighting for their lives.

The authorities have also detained the chairman of a private television channel after it carried a speech by Khaleda Zia's son from self-imposed exile in London.

Security forces say they want to stop violence and are preventing Ms Zia from leaving her party offices in Dhaka to give her "enhanced security".

This bus was set on fire for attempting to travel in defiance of the opposition nationwide transport blockade

Ms Zia and her arch rival, Prime Minister Sheikh Hasina, have both frequently called for general strikes and blockades while in opposition.

Thousands of riot police have been patrolling almost deserted streets in the capital where there were isolated clashes between opposition supporters and police on Tuesday. Authorities have cancelled most bus, rail and ferry services into the city to prevent mass rallies.

Violence broke out in various parts of the country on Monday, and four anti-government protesters were killed.

The opposition are angry that Sheikh Hasina, who has been in power since 2009, refused to stand aside to make way for a neutral caretaker administration to oversee the 2014 election.

Dozens of BNP workers have disappeared since last year's election, with human rights groups blaming the government. The government has denied the claims.

The two women leaders have alternated in power for most of the last two decades when the army was not in government.

Battle of the leading ladies

Khaleda Zia, left, and Prime Minister Sheikh Hasina have been rivals for much of the last 20 years

Political background:

• Sheikh Hasina: Daughter of Sheikh Mujibur Rahman, the first president of Bangladesh

• Khaleda Zia: Wife of assassinated president and BNP founder Ziaur Rahman

Times in power:

• Sheikh Hasina: Served three periods as prime minister between 1996 and today

• Khaleda Zia: Served three stints as prime minister between 1991 and 2006

Why they do not like each other:

• Sheikh Hasina: Awami League supporters say that Sheikh Mujibur was killed by army officers who had links with Ziaur Rahman

• Khaleda Zia: The BNP argues that Ziaur Rahman's role in securing independence from Pakistan is ignored by the Awami League

Reasons for recent tensions:

• Sheikh Hasina: The Awami League says the BNP is closely linked to a hardline Islamist party opposed to secular democracy

• Khaleda Zia: Her supporters boycotted elections in January 2014, arguing that they would have been rigged by the Awami League