Reports: Syria chemical attack responders die

• Up to 1%2C700 people died Wednesday after a rocket attack in East Ghouta%2C a Damascus suburb
• A United Nations team is in Damascus to investigate three earlier reported attacks
• Experts continue to debate what can be learned by watching video of victims%27 symptoms

Some first responders to a reported chemical attack in Syria have died after treating victims, providing more evidence that a weapon of mass destruction was used, opposition forces said Thursday.

"Some of them came down with similar symptoms and passed away," said Khaled Saleh, a spokesman for the Supreme Military Council of the Free Syrian Army, which the United States has provided with non-lethal aid. Saleh said at least six doctors died after treating victims. "We don't have the (total) number of dead first responders yet," he said.

Despite seemingly overwhelming evidence, the Syrian government continues to deny that it used chemical weapons. Three dozen countries, including the U.S., have now called for a United Nations investigation.

Saleh said he learned Thursday that one of the people he had been in touch with Wednesday who was treating people injured in the attack had later passed away.

Between 800 and 1,700 people died Wednesday after a rocket attack on the Damascus suburb of Eastern Ghouta, according to the Syrian opposition, which reported receiving victims in area hospitals and finding more bodies in house-to-house searches Thursday.

Dan Layman, a spokesman for the Syrian Support Group, which supports the Free Syrian Army in Washington, said doctors, nurses and first responders had reported Wednesday that they'd experienced secondary symptoms while working with victims.

"The doctor I was talking to yesterday said the residue on the victims and their clothing was making the doctors get dizzy and have trouble breathing and (they) had to pour water on their faces and had to step out of the room," Layman said.

Layman said he learned Thursday that two of those nurses died.

The reports come as the State Department says the U.S. government is still trying to find out what happened.

"There's a great sense of urgency in the administration to gather information on the ground," State Department spokeswoman Jen Psaki said. "If these reports are true, it would be a flagrant use of chemical weapons by the regime. The president will consider his options and discuss it with his national security team."

President Obama said a year ago, on Aug. 20, 2012, that use of chemical weapons by Syrian President Bashar Assad would cross a "red line" that would prompt the United States to take action that would have "game-changing" impact on the conflict.

The administration determined in June that Syrian pro-government forces had used chemical weapons and that Obama's red line had been crossed. The White House announced it would begin providing lethal aid to the Syrian armed opposition.

Saleh said that aid has yet to arrive.

A United Nations inspection team was in Damascus on Thursday to investigate three sites of earlier alleged chemical attacks, and Secretary of State John Kerry wants that team to have access to the site of Wednesday's alleged attack, Psaki said.

The United States and the U.N. team believe the armed opposition in Syria does not have chemical weapons capability, Psaki said.

"Given the U.N. team is on the ground right now, we're working to put pressure on the Syrian regime to allow access," she said.

One chemical weapons expert looking at the evidence says video from the scenes of the attack are inconsistent with known chemical weapons injuries.

YouTube videos posted by Syrian activists of children gasping for air while being rinsed with water by barehanded medical personnel are not consistent with chemical weapons known to be in the Syrian arsenal, said Dan Kaszeta, managing director of U.K.-based security consultancy Strongpoint Security. Kaszeta worked 20 years on chemical biological and nuclear defense in the U.S. government and military.

Kaszeta said the videos show convulsions that affect some limbs but not all; no skin burns or blisters, which would indicate mustard gas; and no vomiting. He did not have access to any of the victims and his opinions are based solely on the video.

"(With) sarin or nerve agents there would be much more widespread symptoms," he said. "We need physical evidence, blood, urine, tissue, a chest X-ray of one of these guys who died."

Another chemical weapons expert, Hamish de Bretton-Gordon, the former commander of the chemical, biological and nuclear counterterrorism unit at the United Kingdom's Ministry of Defense, says a low-dose chemical weapons attack may explain the absence of some symptoms.

In March 1995, when the Japanese terrorist cult Aum Shinrikyo launched a sarin attack injuring about 6,000 people, first responders who were not present for the attack but treated victims later also experienced symptoms, Bretton-Gordon said.

Saleh said activists in the vicinity of Wednesday's attack have collected samples of victims' hair and blood, of soil and of pieces of munitions that landed in the area, but getting them to someone who can analyze them is another matter.

"The challenge is getting them out," Saleh said. "That area is completely surrounded by Assad's forces. You can't even get wheat in there to make bread."

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