Islamabad, Sep 14 (DPA) At least 20 Taliban militants were killed in a suspected US drone strike and attacks carried out by Pakistani troops in the country's restive northwestern region Monday, officials said.

A missile allegedly fired by an unmanned US aircraft targeted a vehicle believed to be carrying Taliban fighters in the North Waziristan tribal district near the Afghan border.

'Four militants were killed and at least five others wounded,' a local intelligence official said on condition of anonymity.

It was not immediately clear whether any high-profile target was hit in the assault which took place at around 6 a.m. local time.

It was the third missile strike in the North Waziristan region within a week as two simultaneous aerial raids last Monday and Tuesday killed at least 15 militants, including Uzbek fighters.

Pakistan publicly opposes US drone strikes inside its tribal territory, saying they violate its sovereignty.

Officials in Islamabad argue that the assaults are counter-productive in the fight against militancy, as they fuel public criticism of US operations against Taliban insurgents.

Pakistan's tribal region is considered a hotbed of Al Qaeda and Taliban fighters, who use the rugged lands to plan and launch attacks.