While the attacks haven't been claimed by al Qaeda, the attacks show the hallmarks of an al Qaeda operation. The attacks were carried out within hours of each other, used methods designed to cause mass casualties and mass media attention, and targeted a tribal leader opposed to al Qaeda's operations in the region. Multinational Forces Iraq breaks down the timing and targets:

The first suicide truck bomb containing chlorine detonated at a check point northeast of Ramadi at 4:11 p.m., injuring one Coalition service member and one Iraqi civilian.

The second explosion occurred at 6:36 p.m., 17 km south of Fallujah near the town of Amiriyah. The Amiriyah Police Department reported that two policemen were killed in the blast and estimated that as many as 100 local citizens showed signs of chlorine exposure.

The third explosion occurred 37 minutes later at 7:13 p.m., 5 km south of Fallujah in the Albu Issa region when a suicide bomber detonated a dump truck containing a 200 gallon chlorine tank rigged with explosives. Coalition Forces responded to the attack and found approximately 250 local civilians suffering from symptoms related to chlorine exposure.

One item of note: The Albu Issa tribe, which is largely settled in the Albu Issa region of Fallujah, is supportive of the Iraqi government and U.S. forces. Several of the senior officers and a quite a few policemen I met while embedded with the Military Transition Team in Fallujah were from the Albu Issa tribe.

Al Qaeda in Iraq has targeted Sunni opposition in the cities of Ramadi, Fallujah and Amiriya in the recent past. The Ramadi home of Shiekh Abdul Sattar Abu Risha, the leader of the Anbar Salvation Council, was targeted with a multi-pronged suicide attack on February 19th. On March 1st, Amiriya was the scene of a mass attack by al Qaeda in Iraq against a leader of the Anbar Salvation Council. The Anbar Salvation Council is spreading into Fallujah, where al Qaeda has conducted a campaign to collapse the local police and Iraqi Army since U.S. forces withdrew from the city late last year.

Al Qaeda has issued instructions and implored its operatives to use chemical weapons in the past.

On February 20, five were killed and 140 sickened after a chlorine attack in Baghdad. On February 21, a chlorine attack in Taji killed 9 and made 150 sick. On January 28, 16 were killed in chlorine bombing attack in Ramadi. "Suicide car bombers have used chlorine against Iraqis in Al Anbar a total of five times since January 28," notes the Multinational Forces Iraq press release. Chlorine gas is readily available in Iraq as it is used for water purification and a wide variety of industrial uses.

Two chlorine bomb factories were discovered in Karma and Fallujah by Coalition forces on February 21. Karma has increasingly become a hot spot in Anbar province. A Marine CH-46 was shot down with an al Qaeda anti-aircraft missile in Karma, and the follow on task force of U.S. Army engineers sent to secure the wreckage lost three soldiers in a sophisticated IED strike.

As the Anbar Salvation Council continues to oppose al Qaeda's presence in the province, al Qaeda's attacks will become more deadly. The chlorine attacks will not abate anytime soon.