Nearly 350 hostages were rescued at the end of a deadly standoff between Pakistan’s military and armed militants who hijacked a train in the southwestern Pakistani province of Balochistan, a security source told CNN Wednesday.

Pakistan’s prime minister traveled to restive southwestern Balochistan province to meet survivors of a train attack and the commandos who rescued over 300 passengers from the insurgents who killed 21 civilians and four troops.

The Balochistan Liberation Army claims it killed 6 security forces and seized a Pakistani passenger train carrying about 500 people in a remote, mountainous region.

The separatist Baloch Liberation Army claimed responsibility for attacking the train carrying 440 passengers in a tunnel in a remote part of Balochistan. Spokesman Jeeyand Baloch had said the group was ready to free passengers if authorities agree to release jailed militants.

Mehboob Hussain was riding the train home on Tuesday when the tracks under the front car exploded. In the depths of central Pakistan's Bolan Pass, a pocket of wilderness so remote that there is no internet or mobile network coverage, the nine-coach Jaffar Express ground to a halt. Then the bullets started flying.

Separatist militants fired at a passenger train in southwestern Pakistan on Tuesday, injuring a train driver, police and railway officials said.

Hostages freed after a day-long ordeal following an attack by militants on a train in Pakistan's Balochistan province described crouching on the floor for hours before their release, as the bodies of 25 people killed arrived in Quetta.

He was one of more than 400 passengers travelling from Quetta to Peshawar on Tuesday when the Balochistan Liberation Army (BLA) attacked and took a number hostage. Rescue operations are continuing. Military sources claim 155 passengers have been freed and 27 militants killed.