Pakistan’s Prime Minister Shehbaz Sharif was in the restive southwestern Balochistan province on Thursday to meet survivors of a train attack and the commandos who rescued over 300 passengers from insurgents who killed 21 civilian and four troops.

ISLAMABAD — Pakistan’s neglected southwestern province of Balochistan has been the scene of a yearslong insurgency, with a dramatic uptick in attacks in recent years underscoring the struggles the government in Islamabad faces in dealing with myriad security threats.