Explosions believed to have been caused by suicide bombers hit three hotels in Jordan on Wednesday, killing at least 67 people and wounding more than 150 others.

The coordinated blasts, all in Amman, started around 8:50 p.m. local time (2:50 p.m. EST). The first occurred at the Grand Hyatt hotel, followed shortly by explosions at the Radisson SAS Hotel and Days Inn Hotel. Televised reports said at one hotel, a bomber blew himself up at a wedding party.

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The hotels are popular with Westerners, but a Jordanian official said most of the victims were from Jordan. All government offices and schools in the country will be closed on Thursday.

Jordan is a close U.S. ally and has aggressively pursued militant Islamic terrorists operating in and around the Hashemite Kingdom. In July, Jordanian prosecutors indicted five men for allegedly conspiring to attack intelligence agents, tourists and hotels in Amman, the Associated Press reported.

On Aug. 19, three Katyusha rockets were fired at a U.S. Navy ship docked at the Red Sea resort of Aqaba.

Jordan has also sentenced Abu Musab al-Zarqawi, the Jordanian-born leader of al Qaeda in Iraq, to death in absentia. No group has yet claimed responsibility for Wednesday's attack but al-Zarqawi's group or a related terror cell are likely suspects.

Major U.S. markets dipped in reaction to news of the attacks but closed in positive territory. The Dow Jones Industrial Average rose 6 points to 10,546, the S&P 500 was higher by 2 points to 1221.84, and the Nasdaq Composite was up 4 points at 2176.