Security forces in Bangladesh have arrested the son of ex-Prime Minister Khaleda Zia as part of the interim government's crackdown on corruption.
Mr Rahman is one of the most high profile politicians to be arrested
Tarique Rahman and several other politicians were detained during raids in the capital, Dhaka.
The interim government has vowed to clean up corruption before new elections can be held.
Polls set for 22 January were postponed after months of violence and claims that the vote was being rigged.
On Thursday, the authorities banned all indoor political activity, having earlier forbidden all street protests, meetings or political gatherings.
An Interior Ministry statement said some political parties had been found to be misusing the limited freedom they had been allowed.
More than 40 people died during the violent protests, and a state of emergency was declared on 11 January.
The BBC's John Sudworth in Dhaka says Mr Rahman's arrest is a sign that Bangladesh's emergency government, which took power after January's cancelled general election, appears determined to investigate allegations of graft as a precondition to restoring democracy.
Mr Rahman is one of the most high profile of the political heavyweights arrested over the past four weeks, our correspondent says.
Son of the most recent Prime Minister Khaleda Zia, he is also senior joint secretary of the Bangladesh Nationalist Party and has been widely accused by the country's media of involvement in corruption.
Some politicians are accused of acquiring luxury properties
"Military-led security forces arrested Tarique Rahman from his home. He is now under their custody," police officer Saiful Alam told the AFP news agency.
A total of 30 former ministers, political advisors, businessmen and bureaucrats are now in prison. Their luxury cars have been seized and their bank accounts frozen.
The latest raids also included a search of the house of another of Bangladesh's former prime ministers, Sheikh Hasina, although no arrests were made.
However, the Awami League Mayor of Chittagong, ABM Mohiuddin Chowdhury, was arrested.
On Tuesday, a court extended for another month the detention of the politicians and businessmen arrested on charges of corruption.
Over the last five years, Bangladesh has been listed by the anti-corruption watchdog, Transparency International, as one of the corrupt countries in the world.