Cologne Cathedral, which has been heavily guarded following a terror alert, will be protected by police officers until further notice, even after the New Year celebrations passed without incident. “There will continue to be security checks at the cathedral,” a police spokesman said on Monday. “How long this measure will be maintained is currently under review.” Police officers will continue to be seen at the cathedral for the time being, the spokesman said. Shortly before Christmas, the police received information about a possible Islamist plan to attack Cologne Cathedral on New Year’s Eve, le…