DHAKA (Agencies) - A mutiny by thousands of Bangladesh border guards ended in their surrender Thursday, as the tanks surrounded Bangladesh Rifles headquarters after a second day of gunfire in a mutiny that killed about 50 people. But uncertainty remained over the fate of more than 130 army officers still missing after rank-and-file guards in the paramilitary Bangladesh Rifles (BDR) took them hostage in a dispute over pay and conditions. Government officials and police said the mutiny in Dhaka was under control and urged members of the BDR border guards who had mutinied elsewhere in the country over pay and command issues to lay down their arms. Gunfire in the capital gradually subsided and stopped after Prime Minister Sheikh Hasina threatened warned the mutineers were on a "suicidal" path that could only end in bloodshed. "All the troops have surrendered their weapons and gone back to their barracks," the Prime Minister's spokesman, Abul Kalam Azad, told AFP, adding that all remaining hostages had been freed. At least 20 government tanks and 15 armoured personnel carriers ringed the BDR headquarters in Dhaka, where nearly 50 people were killed in Wednesday's violence. Hundreds of BDR mutineers handed over their weapons, including automatic rifles, machineguns and grenades, to police who locked the weapons inside two armouries in the BDR complex. "Police have locked the armouries and handed me the keys after the troops completed the surrender," Home Minister Sahara Khatun told reporters outside the BDR headquarters, where the mutiny broke out on Wednesday. But a spokesman for the armed forces who did not wish to be named said only 31 of the 168 officers inside the compound when the mutiny began were accounted for. "We don't know what happened to the rest of the 137 officers. They are still missing," he said. Tensions in the BDR had been simmering for months but exploded into violence early Wednesday when senior officers dismissed appeals for more pay, subsidised food and holidays. Police have put the official death toll at 20 with dozens more injured, although one Minister earlier said that as many as 50 officers may have been killed by their men. Among the missing was the head of the BDR, Maj-Gen Shakil Ahmed, who was Thursday reported to have been shot dead during the rebellion. "Maj-Gen Shakil Ahmed was among the first to be killed by the mutinous soldiers. They shot him dead at the Durbar Hall," his colleague Col M Kamruzzaman told private TV station ATN Bangla. In a televised address to the nation, Premier Sheikh Hasina, who took office less than two months ago, threatened to put down the mutiny by force. "Just give up your arms and return to barracks right now," she said. "Don't take the suicidal route. Don't compel me to take tough action. We are aware of your problems. Please help us." Earlier Thursday, the revolt appeared to be spreading to a number of other BDR posts outside the capital. Police chiefs across the country said BDR members had revolted in 15 border districts - roughly a quarter of the zones where border security forces are stationed. Police chief Kamrul Ahsan, from the southeastern town of Satkania, reported "heavy fighting" at a BDR training centre. In an effort to stem any further spread, the Bangladesh telecoms authority ordered all the country's six mobile operators to shut down their networks. "Keep the peace and stay patient for the sake of the nation. I urge everyone to be patient. I seek cooperation of all," she said in her televised address. The mini-revolt highlighted the frustrations felt by many in Bangladesh, which suffers from high food prices, a slowing economy and rampant corruption within the ruling classes.