Terrorists in explosive vests have reportedly threatened Pakistan train passengers' lives if officials refuse to release imprisoned 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.

The Baloch Liberation Army, a militant group seeking secession of the province from Pakistan, had claimed responsibility for the attack.