The militants, Baloch ethnic fighters, said they would kill dozens of seized security personnel if the Pakistani government did not agree to a prisoner exchange.

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.

Home to about 15 million of Pakistan’s estimated 240 million people, according to the 2023 census, Balochistan remains the country’s poorest region despite being rich in natural resources such as coal, gold, copper, and gas. These resources generate substantial revenue for the federal government.