Eighteen people have been killed and hundreds injured in a number of explosions at a big opposition rally in the Bangladeshi capital Dhaka.
The blasts tore through the crowd without warning
There were seven or eight explosions soon after opposition leader Sheikh Hasina addressed a crowd.
About 200 people were hurt in the blasts and the chaos that ensued, when angry crowds set fire to buildings and cars and were beaten back by police.
Prime Minister Khaleda Zia condemned what she called a "dastardly attack".
The explosions began at about 1725 local time (1125 GMT) on Saturday as Ms Hasina, a former prime minister, stood on the back of a truck to address about 20,000 people outside the Awami League headquarters,
No-one has yet claimed responsibility for the explosions.
'Crying for help'
Witnesses said many of those hurt in the blasts were badly wounded.
"People were covered with blood, many injured were crying for help," rickshaw driver Mohamad Yasin told the Associated Press news agency.
Rafiqur Rahman, a Reuters news cameraman at the scene, said: "I heard several blasts and people were just fleeing."
Demonstrator Muhammad Alamgir described the pandemonium: "Everything was smoke. I couldn't see anything.
"People were running. I was so scared I couldn't move. I just sat down and people were running over me," AFP news agency quoted him as saying.
Several senior league officials were wounded. Ivy Rahman, the party's other most prominent female leader, lost both her legs.
Ms Hasina, who was slightly hurt, told the BBC she was protected by her supporters, some of whom were killed.
"When the attackers started hurling grenades towards the makeshift podium on a lorry, my workers saved me by sacrificing their lives," she said.
Ms Hasina accused the government of attempting to assassinate her and demanded it resign for failing to protect innocent people.
A government spokesman said the blasts appeared aimed at destabilising Prime Minister Zia's administration.
The Awami League called for a general strike on Tuesday and Wednesday to protest against the attack.
Police and troops are patrolling the streets in central Dhaka, where demonstrators shouting anti-government slogans gathered.
There have also been outbreaks of violence in about a dozen other towns and cities and security has been stepped up across the country.
The attack in Dhaka is the latest in a series of blasts in Bangladesh this year, including one which killed an Awami League leader in the town of Sylhet on 7 August.
The rally in Dhaka had been called to protest against the attack in Sylhet.
Police have so far not arrested anybody in connection with any of the attacks this year.