"Let me tell you all again that the Bangladesh army is subservient to the government," Army Chief General Moeen U Ahmed said.

"We are a people's army serving the nation and upholding democracy. Please stay calm. We are trying to address the situation and resolve (disputes) with the help of everyone," he said after a meeting with Hasina at her residence late on Friday.

The impoverished South Asian nation has suffered several military coups since independence in 1971. This week's mutiny by Bangladesh Rifles (BDR) border guards was over pay and command and was not politically motivated, officials said.

The mutiny came as a stern test for Hasina, who took office last month after winning elections in December that brought to an end two years of emergency rule by an army-backed government.

Hasina has the task of trying to convince much-needed foreign investors and aid donors she can bring stability to a country where 40 per cent of the 140 million population live in poverty.

The mutiny ended late on Thursday when the rebels laid down their arms after an amnesty offer, made by Hasina late on Wednesday, was followed by threats of stronger action as regular troops, backed by tanks, surrounded the BDR complex in Dhaka.

Hasina's long-standing rival, Opposition leader and former premier Begum Khaleda Zia, offered to cooperate with the government in its investigations into the mutiny but criticised Hasina for offering the BDR rebels an amnesty.

"This gave them time to kill more people and conceal their brutality," Khaleda said late on Friday.

More than 50 bodies were recovered on Friday, many from a mass grave, with BDR commander Major-General Shakil Ahmed among the dead. Two more mass graves were found on the BDR compound on Saturday, and diggers said they already found 10 bodies and expected more.

BDR officers are usually drawn from regular army units and the mutiny was launched as officers arrived for a meeting.

An unknown number of people were still missing and the death toll could rise to more than 100, officials have said.

Moeen said the deaths of so many army officers was an irreparable loss for the Army and the country.

He spoke as rumours swirled through the capital that he might step down or that the Army might launch ‘reprisal’ strikes over the killing of so many of their colleagues.

Former Army Chief Lieutenant-General Harunur Rashid warned that the mutiny might not be an isolated incident.

"It may be a conspiracy to destroy the progress of the new democratic government," Rashid told the ‘Prothom Alo’ newspaper.

As the search for victims and survivors went on, a day of mourning was observed on Saturday, with flags flown at half mast across the country and special prayers said for the dead.

In Dhaka, activity on the streets appeared normal. Offices and schools were closed for the weekend.

Home Minister Shahara Khatun said there was no fear of a deterioration of law and order or a repeat of the mutiny, which spread to about a dozen smaller towns across Bangladesh.