Pakistani intelligence officials say a suspected U.S. missile strike has killed at least four militants in the country's restive northwest tribal region.

The strike occurred Wednesday near the town of Miranshah in North Waziristan, along the Afghan border.

The officials said a suspected U.S. drone fired two missiles at a vehicle carrying Taliban fighters.

Covert U.S. missile strikes in Pakistan's tribal areas have targeted top Taliban and al-Qaida commanders. U.S. officials do not publicly comment on such attacks.

Pakistani officials have publicly protested the strikes, which they say anger the public and undermine the country's military campaign against the Pakistani Taliban.

Also on Wednesday, the International Monetary Fund said it will release the next portion of its $11.3 billion loan to Pakistan at a board meeting May 3.

Prime Minister Yousuf Raza Gilani says he aims to keep the budget deficit close to 5.1 percent.  

The IMF has so far given about half of the loan, as part of an aid deal reached last year to increase Pakistan's cash flow and stabilize its economy.

Some information for this report was provided by AP, AFP and Reuters.