At least 33 workers were abducted by militants from their cars and pickups in northwest Pakistan's tribal area on Saturday, local officials told Xinhua.

According to local officials, Water and Power Development Authority (WAPDA) workers were kidnapped by some unknown militants when they were returning from Kurram Agency, a tribal region in the Northwest of Pakistan.

They went to the Kurram Agency for some electricity installation but they were kidnapped on the way back to office.

Militants have set one of their vehicles on fire and took them to unknown places.

Gunfire is also continuing between police and kidnappers as policemen are following them, sources said.

Earlier reports said some 60 people were kidnapped.