LADHA: Missiles fired by US drones hit three 'targets' in South Waziristan Agency on Monday, killing 17 suspected militants, official sources said, adding that five of the deceased were foreigners.

The first strike was reported in Wacha Dana, some 15km west of Wana, at around 2am. Three missiles hit a residential compound owned by a tribesman, Rozi Khan Shamshikhel, leaving seven people dead, officials said.

Although their names could not be known, the men killed in the attack belonged to Punjab.

Five Arab nationals died when drones targeted a seminary in the same area. A local cleric, Maulvi Sakhi Merjan, ran the seminary.

A missile struck a pickup truck in Dery Nashter area adjacent to North Waziristan. Five people on board were killed, officials said. AFP adds:

US missiles killed 18 militants in South Waziristan on Monday, destroying compounds and a vehicle in the deadliest drone strikes for months, local officials said.

An official warned the death toll could rise. The combined toll of 18 made Monday's drone strikes the deadliest reported in the country since a salvo of US missiles killed at least 35 people on March 17.

US drones have reportedly carried out 12 strikes in tribal belt since US commandos killed Al Qaeda founder Osama bin Laden in a raid in Abbottabad on May 2.