PESHAWAR, Pakistan — A roadside bomb hit a convoy of foreign diplomats visiting northwest Pakistan on Sunday, killing a police officer in their security detail, police said.

Zahidullah Khan, a police officer from the Swat district, told NBC News that the diplomats were on their way to a tourist resort “when a police van escorting their convoy was hit by an improvised explosive device.”

One police official died on the scene and three others were injured, he said, adding that the…