Published: Oct 30, 2010 4:24 PM EDT
Updated: Oct 30, 2010 1:24 PM EDT

WASHINGTON (AP) - Yemeni authorities say they are checking dozens more packages in a search for the terrorists who tried to mail bombs to Chicago-area synagogues.

An official earlier said that some of the packages had made I out of the country now says the search is centered in Yemen's capital. A second Yemeni official describes the search as precautionary and says there are no indications the packages contain explosives. He said authorities also hope the searches would help gather evidence in their hunt for the bombers.
      
Authorities on three continents thwarted the attacks when they seized explosives on cargo planes in the United Arab Emirates and England yesterday. The plot prompted searches of planes and parcel trucks for other explosives. Officials temporarily banned all new cargo from Yemen.

Several U.S. officials say they believe that al-Qaida's Yemen branch, the group behind the failed Detroit airliner bombing last Christmas, is responsible.

President Barack Obama has called British Prime Minister David Cameron and Saudi Arabia's King Abdullah to discuss the thwarted mail bomb attacks.
      
White House spokesman Bill Burton says the president also received a briefing Saturday from his national security adviser, John Brennan.
      
Obama is campaigning Saturday in Bridgeport, Conn., Philadelphia and Chicago.