Nearly 350 hostages have been 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.

Baloch separatist militants blew up a railway track and launched rockets at the Jaffar Express, which was carrying over 400 passengers.

After more than a day of fighting with separatist militants who hijacked a train carrying hundreds of passengers, Pakistan’s army said it had brought the insurgent attack to an end, but that 21 passengers and four paramilitary personnel had been killed.