U.S. President Barack Obama on Tuesday expressed deep concern about the attack on the Sri Lankan cricket team in Pakistan, saying the country's frontier regions still is the safe heave for terrorists.

"Obviously, we are deeply concerned," Obama told reporters in the White House after meeting with visiting British Prime Minister Gordon Brown, according to Xinhua News Agency.

The U.S. State Department too condemned the attack, which was the first deadly attack targeted a foreign sports team in Pakistan.

"We condemn this vicious attack on innocent civilians but also on the positive relations that Pakistan and Sri Lanka are trying to enjoy," said deputy spokesman Gordon Duguid. "This is an attack on peaceful, normal relations, and we utterly condemn this terrorist attack."