ISLAMABAD, Feb. 7 (Xinhua) -- on Wednesday pledged to arrest the killers of a Chinese national who was gunned down in the southern port city of Karachi on Monday.

Police said unknown assailants had fired at the Chinese national's car in Karachi's Defense locality.

The foreign ministry said it condemned the killing "in strongest possible terms."

"Pakistan will take all possible measures to apprehend the culprits and carry out thorough investigation against perpetrators of the crime," foreign ministry spokesman Mohammad Faisal said on his Twitter.

Police had said earlier that the assailants had fled from the scene after the attack.