Syrian forces killed up to 30 worshippers near a mosque in Hama on Tuesday, opposition activists said.
According to Reuters, the activists reported that government troops and pro-government militants fired on worshippers as they converged on a mosque for evening prayers on Ramadan.
"Troops and Shabiha (militia loyal to President Bashar al-Assad) left the roadblock on the edge of Shariaa and crossed the main road and began firing automatic rifles at the worshippers as they were entering the mosque," said Jamil al-Hamwi, one of the activists.
He told Reuters by phone, "We have confirmed the names for 15 bodies and there is a similar number estimated still to be collected from the streets."
The news comes as reports from Aleppo suggest that Syrian forces used fighter jets in their offensive against rebels, a first in this conflict. The BBC said one of its correspondents near Aleppo reported fighter jets bombing the eastern part of the city, a significant escalation in the conflict.
Rebels launched an offensive in Aleppo over the weekend, while fighting continued in Damascus. Government troops launched shells and rocket fire in Aleppo as their forces attempted to wrest back control as they claim to have done in Damascus.
Speaking to reporters in Washington, US Secretary of State Hillary Clinton said, "We have to work closely with the opposition, because more and more territory is being taken," according to the BBC.
According to the pro-opposition Local Co-ordination Committees, at least 90 people were killed on Tuesday, including 20 in Aleppo.
The rebel Free Syrian Army on Tuesday accused Assad of moving chemical weapons to Syria's border, according to Agence France Presse.
In a statement, the FSA said, "According to our information, the regime began moving its stocks of weapons of mass destruction several months ago… with the goal of putting pressure on the region and the international community," according to AFP.
On Monday, foreign ministry spokesman Jihad Makdissi confirmed that Syria did possess chemical weapons but would only use them against foreign attackers, not against its own civilians.
President Barack Obama responded to the news, saying, "They will be held accountable by the international community and the United States should they make the tragic mistake of using those weapons," according to AFP.
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Assad also appointed a new security chief and senior intelligence officials on Tuesday, following the bomb attack last week which killed four members of his inner circle, according to the Associated Press.
Maj. Gen. Ali Mamlouk was appointed as the head of the National Security Council, and Maj. Gen. Abdel Fattah Qudsiyeh was named the council's deputy chief, said the AP, citing an official.
Longtime Assad aide Maj. Gen. Rostom Ghazali was named the head of the Political Security Department and Maj. Gen. Deeb Zeitoun will head General Intelligence. Maj. Gen. Rafiq Shehadeh was appointed the new head of Military Intelligence, according to the official.
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