BEIRUT (AP) -- Syrian government forces battling insurgents carried out a series of airstrikes on Wednesday on a city in southern Syria that has been declared a safe zone under a recent Russia-sponsored deal, opposition activists and an independent monitor said.
The Britain-based Syrian Observatory for Human Rights said government forces carried out at least 12 airstrikes and dropped at least nine barrel bombs on rebel-held parts of Daraa as intense clashes with insurgents, including members of the al-Qaida-linked Levant Liberation Committee, continued in the city's Manshiyeh neighborhood.
The monitoring group added that at least two rockets were launched by government forces in the area.
The activist-run Step News Agency and Qasioun News Agency also reported clashes and shelling in the southern city.
Russia, Iran and Turkey agreed to establish the zones in Syria, signing on to a Russian plan under which President Bashar Assad's air force would halt flights over designated areas across the war-torn country.
This week's clashes are among the worst violations of the so-called de-escalation agreement.
Intense clashes in Daraa began on Monday between government forces and insurgents with both sides shelling parts of the southern city.
Daraa, where protests against Assad's rule first began in March 2011, is one of four "de-escalation zones" announced earlier this month during cease-fire talks in Astana, Kazakhstan.
Russia's defense minister, meanwhile, said the deal to set up the zones is "the main document to end Syria's civil war."
Sergei Shoigu said Moscow has been discussing safe zones in Syria with several nations, including the United States, Israel and Jordan.
Shoigu said Russia has been working with Turkey and Iran to prepare for the deployment of a monitoring force to patrol safety zones once all the specifics are set at next month's meeting in Astana.