MADRID, Jan. 18 (Xinhua) -- Spanish police on Saturday arrested 14 suspected Islamic extremists in Barcelona, the Interior Ministry said.

    The Spanish civil guard police searched several homes in Barcelona with the National Intelligence Center, Spain's home intelligence services, the Interior Ministry said in a statement.

    It added that more arrests have not been ruled out.

    Prime Minister Jose Luis Rodriguez Zapatero has confirmed the arrests and said investigations were undergoing.

    Interior Minister Alfredo Perez Rubalcaba is expected to hold a news conference at 1230 local time (1130 GMT) to provide further details on the operation.

    Spanish police have stepped up anti-terrorism operations since the March 11, 2004 train bombings in Madrid.

    The attacks on railway carriages during the morning rush hour near Madrid's Atocha station killed 191 people and injured more than 1,800 others.