Taliban insurgents set fire yesterday to about 200 oil tanker trucks supplying fuel for Nato forces in an attack just outside Kabul, police said.

TV footage showed black smoke billowing above the site, with the charred wreckage of dozens of trucks spread around.

It was unclear how the fire was started. Some Afghan media reported that insurgents had fired rockets at the tankers. There were no immediate reports of casualties.

The attack came as Afghanistan prepares to announce preliminary results of the final round of the presidential election tomorrow.