After a weeklong military campaign in Syria to bolster the government of President Bashar al-Assad, Russian airstrikes have hit three medical facilities in the country’s northwest, in what experts say is a continuation of four years of attacks on health care facilities in rebel-held territories in the country.

The New York-based Physicians for Human Rights (PHR) identified three strikes on Oct. 2 and 3, that occurred in the provinces of Hama, Idlib and Latakia. The strikes caused injuries, damages to the facilities and hampered desperately needed services, the group said.

“Bashar al-Assad’s forces have been relentlessly attacking Syria’s health care system for the past four years and the Russian government is now following in their footsteps,” Widney Brown, PHR’s director of programs, said in a press release. “With these actions, Russia is damaging hospitals, putting patients and medical staff at risk, and depriving civilians of life-saving access to health care.”

PHR has documented 307 attacks on medical facilities in Syria since the start of the conflict in 2011. It says more than 90 percent of those attacks were perpetrated by Syrian government forces. Intentionally targeting medical facilities constitutes a war crime under the Geneva Conventions, they point out.

According to PHR, the Syrian government attacked two of the facilities with barrel bombs earlier this year.

PHR said the strikes hit more than 30 miles from territory held by the Islamic State in Iraq and the Levant (ISIL), suggesting that the attacks were aimed at land controlled by other Syrian rebel groups.

Russia's military involvement in Syria appeared to escalate sharply on Wednesday, with Moscow launching cruise missiles from the far-away Caspian Sea while also backing Syrian government troops on the ground in fighting against Syrian rebel groups.

Russia started its air campaign in Syria saying it would only target ISIL, but its mission has been a broad-based campaign to support Assad against a variety of rebel groups, including those who have received U.S. backing, Syrian activists and U.S. officials say.

The Russian government did not confirm that its strikes hit the medical facilities, but did say it had been targeting the areas in which the facilities are located, the group said.

The allegations against Moscow come amid an international outcry over the U.S. bombing of a medical facility in Afghanistan operated by Doctors Without Borders, an incident for which PHR has also called for an independent investigation.

Russia last week rejected claims that its bombing campaign in Syria had led to civilian deaths, but the anti-Assad Syrian activist group Syrian Observatory for Human Rights said last Friday that at least 30 civilians had been killed in the first two days of Russian air strikes.