Russia says two of its combat helicopter pilots were killed in Syria's central Homs province when they ran out of ammunition in their Mi-25 aircraft and were hit by Islamic State ground fire.
The official Tass news agency said the shoot-down occurred Friday east of the city of Palmyra, after government forces requested air cover. Tass also said that reserve units were not available in the area for redeployment to the scene as IS fighters advanced on the government troops.
To the north, meanwhile, monitors said fierce clashes erupted for a second straight day Saturday near Aleppo, Syria's largest city, where the Damascus government had promised to extend through Monday a cease-fire honoring the end of the Muslim holy month of Ramadan.
The Britain-based Syrian Observatory for Human Rights said rebels fighting alongside al-Qaida's Syrian affiliate, the al-Nusra Front, launched a counterattack late Saturday to reopen a supply route seized by government forces two days earlier. There were no immediate reports about the extent of the fighting or casualties.
Observatory monitors said more than 40 people were killed in Aleppo and in nearby Idlib province on Friday. At least 23 victims, including several children, were killed in airstrikes in Idlib, but it was not clear whether Syrian or Russian warplanes were responsible.
The extended Eid al-Fitr cease-fire is set to expire at midnight July 12, but observers say the truce has been repeatedly violated since it began Wednesday.