|Information on the drone attacks in the North Waziristan tribal belt is very hard to verify independently
Suspected US missiles have struck two vehicles in a Taliban stronghold on Pakistan's side of the border with Afghanistan, killing 18 alleged fighters.
Pakistani intelligence officials said the missiles struck the vehicles in the Shera Tala village of the North Waziristan tribal region on Monday. Shera Tala lies in Mir Ali district, where fighters are heavily concentrated.
The exact identities of the 18 dead were not immediately certain.
The vehicles were apparently leaving a compound, and one was carrying a large load of ammunition, magnifying the blasts from the missile attacks, the intelligence officials said.
The attacks appear to be a part of an accelerated campaign to take out al-Qaeda and Taliban fighters seeking sanctuary outside Afghanistan.
At least 110 such missile attacks have been launched this year - more than doubling last year's total. Nearly all have landed in North Waziristan, a region that hosts several armed groups battling US and NATO troops in Afghanistan, including the Haqqani network.
Pakistan officially condemns the drone attacks, saying they violate its sovereignty and anger tribesmen.
But the country is widely believed to secretly support the operations and provide intelligence for at least some of them.
US officials rarely discuss the covert CIA-run missile programme. Privately, however, they say it is a crucial tool and has killed several important pro-Taliban leaders. They also say the drone-fired strikes are very accurate and usually kill fighters.