AN EXPLOSION IN THE BASEMENT OF A BUILDING INJURED SEVERAL PEOPLE IN ISTANBUL ON THURSDAY, THE ANATOLIA NEWS AGENCY AND TURKISH TELEVISION REPORTED. THE EXPLOSION OCCURRED IN THE DISTRICT OF USKUDAR ON THE ASIAN SIDE OF THE CITY. THE CAUSE OF THE BLAST WAS NOT IMMEDIATELY CLEAR. AMBULANCES WERE SEEN RUSHING TO THE SCENE, REPORTS SAID.