WAMIS, Libya (Reuters) - Rival militias in an area south-west of the Libyan capital exchanged heavy gunfire on Monday after a dispute flared up between them that local residents said had killed at least four people over the past 48 hours.

Reuters journalists in Wamis, about 190 km (120 miles) from Tripoli, said the fighting was between members of the El-Mashasha tribe, based around the town, and fighters from the larger town of Zintan in the mountains to the north.