The Syrian Air Force carried out some 15 strikes in and around the central city of Palmyra early on Monday, targeting buildings captured by the hardline Islamic State group from the military, a group monitoring the war said.
Islamic State have executed close to 220 people, including children, in the area since May 16, the Britain-based Syrian Observatory for Human Rights said.
The air force carried out raids on targets including the military intelligence building and the city hospital.
– Observatory founder Rami Abdulrahman
Islamic State supporters have posted videos online which they say show fighters raiding government buildings in Palmyra, searching for troops and pulling down pictures of President Bashar al-Assad and his father.
They have also posted pictures claiming to show the Islamic State flag raised over the ancient citadel in Palmyra which they had seized on Wednesday.
The White House has said the seizure of Palmyra was a setback in the fight against Islamic State, but spokesman Josh Earnest said President Barack Obama disagreed with Republicans demanding he send ground troops to fight the group.
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