Security is tight in Dhaka as relatives wait for news
At least 200 members of Bangladesh's border force involved in a two-day mutiny have been arrested while trying to escape, security officials say.
The Bangladesh Rifles guards tried to flee dressed as civilians from their HQ in the capital Dhaka, where the mutiny began, a spokesman said.
Soldiers are searching the compound for more than 130 senior officers who were held hostage and are feared dead.
The known toll has risen to 40 with the discovery of around 20 more bodies.
The government has offered the border guards a general amnesty although that is unlikely to extend to the ringleaders of the mutiny or those responsible for killing the officers, the BBC's Mark Dummett in Dhaka says.
Announcing the capture of the fleeing guards, Commander Abul Kalam Azad of the elite Rapid Action Battalion said checkpoints had been set up at roads leading out of Dhaka and surrounding the border guard barracks.
"We are searching buses and trucks for any other rebel troops," he said.
One report said a further 68 mutineers had been arrested north of Dhaka although this was not confirmed.
The border with India has been shut, Indian border security officials in Calcutta told the BBC.
Search of sewers
Troops have entered the Bangladesh Rifles (BDR) headquarters in the hunt for missing officers.
Relatives of the missing officers gather outside the BDR compound
Only 31 of the 168 officers inside the compound have been accounted for, an armed forces spokesman said earlier.
"We don't know what happened to the rest of the 137 officers. They are still missing," he said.
The official toll rose from 22 to around 40 after the bodies of at least 18 senior military personnel were found on Friday.
One regular army officer who managed to escape said the hostage-takers had opened fire indiscriminately.
"It was cold-blooded murder," Syed M Kamruzzaman told AFP news agency.
"They hurled abuse at us and gunned down whoever they wanted. I was shot at seven times and was lucky to get out alive."
He said BDR chief Major General Shakil Ahmed had been shot in front of him, although there is no official confirmation of his death.
Rescue workers are searching sewers and under manhole covers.
Worried relatives of both the officers and the mutineers have gathered at the Dhaka headquarters waiting for news.
Seven BDR troopers were also killed in the clashes, along with four civilians, including one boy.
Along with its headquarters in Dhaka, the BDR has nearly 70,000 men stationed at 42 camps across the country, including 40,000 on the borders.
It is not yet clear if the mutineers at other bases outside Dhaka have also given up.
The crisis began on Wednesday at about 0930 local time (0330 GMT), reportedly after senior BDR officers refused to consider better pay and conditions for the troops.
Rank-and-file BDR members have long been angry over the fact that they earn about $70 (£49) a month, equivalent to the pay of a low-ranking government clerk, while their senior officers, in contrast, are relatively well-paid army officers.
They ended their mutiny on Thursday after tanks surrounded the barracks and Prime Minister Sheikh Hasina offered to consider their grievances.
In a televised address to the nation, Sheikh Hasina called on the guards to abandon what she called their "suicidal action".
"Lay down your guns immediately and go back to barracks," she said.
"Do not force me to take tough actions or push my patience."
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