World leaders are calling on the Assad regime to allow U.N. inspectors into the site, while Syrian opposition activists say the government is launching a major offensive to retake the area.
Syrian government forces are attempting a ground assault on the Damascus suburb of East Ghouta, the site of a suspected chemical attack that opposition activists say killed at least 1,302 people, about half of them women and children according to opposition sources.
The news comes as international pressure on the regime of Syrian President Bahsar al-Assad increased over the alleged attack.
President Obama on Friday called chemical attack reports a matter of "grave concern" that may require action from the international community. And Russia urged Syria's president to allow United Nations inspectors now in Damascus into the area of Wednesday's reported attack to investigate.
French Foreign Minister Laurent Fabius said a "reaction with force" may be needed if the chemical attack on civilians is confirmed. And William Hague, the foreign secretary of the United Kingdom, called Wednesday's attack "a terrible atrocity including the use of chemical weapons."
"This is not something a humane and civilized world can ignore," Hague told Sky News. "Our priority is to make sure the world knows the facts of what happened there."
The Syrian regime blocking the U.N. team's access to the site means that "already it seems the Assad regime has something to hide," he said.
Obama told CNN the conflict in Syria "is something that is going to require America's attention and hopefully the entire international community's attention." Though he also warned against "jumping into stuff, that does not turn out well."
Josh Earnest, Obama's principal deputy press secretary, told reporters Friday that U.S. assistance to the armed opposition in Syria is "expanding in scope and in scale," and that "all options remain on the table when it comes to Syria," except for American boots on the ground.
Earnest would not discuss what options are being considered, however, according to a pool report.
The Syrian Support Group, which assists the Free Syrian Army in Washington, said the attack occurred as many people were sleeping, and that bodies were found in cellars where they took shelter from the artillery barrage. Activists have counted 1,488 dead, while medical personnel confirmed 1,302 deaths, according to the SSG report.
"The dead were loaded into large pick-up trucks by the hundreds and taken to three large mass graves in Zamalka, Ain Turma and Arbeen, according to Mohammad Salaheddine, an activist cited in the SSG report who was based in Zamalka hospital when victims began to arrive Wednesday.
Two nurses at Zamalka medical centers later died after exposure to chemical residue on victims they were treating. Khaled Saleh, a spokesman for the Syrian National Council, the U.S.-supported political opposition, said six doctors and an unknown number of first responders died after treating victims.
REPORTS: Syria chemical attack responders die
Rebel forces have gained greater control of East Ghouta in the past seven to 10 months, despite repeated and failed attempts by the Syrian government forces to dislodge them, according to Dan Layman, spokesman for the SSG.
The chemical attack has been followed by a heavy fighting in East Ghouta's southern neighborhoods, where regime forces backed by Iranian, Hezbollah and other Shiite fighters are "Trying to puncture East Ghouta from the south," Layman said.
"The massive ground offensive following the chemical attacks seems to be an attempt to finally take the area by force," Layman wrote. "Chemical weapons seem to have been used to soften rebel positions, to create mass panic and to occupy opposition forces with civilian casualties as the regime pushes into the area."
FSA forces in East Ghouta are not equipped with heavy weapons and have destroyed only a few regime tanks in recent weeks with improvised mines, Layman said.
Reuters reported that some Syrian activists are smuggling body tissue samples from the reported victims of the attacks to U.N. investigators.
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