Two Chinese nationals were shot at and injured on Tuesday in Pakistan's commercial hub of Karachi, police and hospital officials said, after a string of attacks that spurred Beijing to demand tougher security for its citizens.

Authorities say a Pakistani guard shot and wounded two Chinese nationals working in a textile mill in the southern port city of Karachi, but the attack was not related to militant violence.

A Pakistani guard shot and wounded two Chinese nationals working in a textile mill in the southern port city of Karachi on Tuesday, but authorities said the attack was not related to militant violence.