Four militants, including two foreigners, were killed on Wednesday in a suspected US missile strike in Pakistan's restive north Waziristan tribal region bordering Afghanistan.

US drones fired missiles targeting the house of a local man identified as Dilbar in Indi Khel village in Bannu, which is part of Pakistan's North West Frontier Province, and killed four people including two foreigners, TV channels reported.

According to the reports, those died were militants from Turkmenistan.

Officials confirmed the attack but did not say about casualties and other details. There was no official confirmation about the nationality of the victims.

Television channels said that five other people were injured who were taken to a hospital in Bannu.

District Police Officer of Bannau Alam Shinwari said that investigations into the attack are underway.

The US is blamed in around 20 missile strikes in northwest Pakistan since mid-August.

Pakistan has strongly protested the attacks on its soil terming them as violations of its sovereignty, but the US strikes have not stopped.

Pakistan has said that the strikes are counterproductive because they often kill civilians and simply deepen anti-American sentiment along the border.