At least 10 NATO oil tankers were torched in Pakistan's Sindh province Monday morning, a media report said.
According to Geo News, the incident took place around 2 a.m., when unidentified gunmen opened fire at a NATO supply convoy on the national highway near Khairpur city.
The convoy was on its from Karachi to Peshawar when it came under attack.
The oil tankers caught fire and four people, including three drivers, were seriously injured.
One hotel and three nearby shops also caught fire, police said.
Six fire tenders were called in to put out the blaze.