Putin Assad meeting
Assad made a surprise visit to Moscow on 20 October 2015 to thank Putin for launching air strikes against Islamist militants in SyriaReuters

Russian warplanes have killed at least 13 people, including medical personnel after hitting a field hospital in Syria, the Syrian Observatory for Human Rights has said. The strike took place on the town of Sarmin in the northwestern province of Idlib on 20 October.

"Thirteen people were killed in Russian air strikes on Tuesday on a field clinic, including a physiotherapist, a guard, and civil defence member," the Observatory's head, Rami Abdel Rahman. The strikes were confirmed by staff members of the Syrian-American Medical Society (SAMS), which runs the now "severely damaged" facility.

"Yesterday at around 1:00 pm (11:00 BST) a SAMS facility near Sarmin, Idlib was hit," a SAMS staffer told AFP in an emailed statement. "Our initial reports from the ground show that we have lost two hospital staff, a physiotherapist and a nurse". The SAMS worker - who was speaking on condition of anonymity - did not say whether the warplanes were Russian.

Russia's defence ministry confirmed that a strike on Sarmin did take place, but made no mention of the hospital. Nearly 80% of Moscow's declared targets in Syria have been in areas outside of Islamic State (IS) control, according to a Reuters analysis of Russian Defence Ministry data. The study also revealed that most of the targets have been on locations held by groups - some of whom are backed by the West - opposed to Syrian President, Bashar al-Assad.

Since Russian air strikes began in Syria on 30 September, Russia has hit 64 locations, of which a maximum of 15 were in IS-held areas, according to data compiled by the Institute for the Study of War. "If you look at the map, you can easily understand that they are not fighting Islamic State but other opposition groups," said Alexander Golts, deputy editor of online newspaper Yezhednevny Zhurnal.

Russia has carried out over 500 strikes against what it claims are IS militants, but the Observatory has said that Moscow's bombing campaign has killed 370 people, of whom 127 were civilians. More than 250,000 people have been killed and 11 million more have been forced from their homes since the Syrian war began in 2011.

Assad thanked his Russian counterpart, Vladimir Putin for his military support during a meeting in Moscow on 20 October. According to a transcript released by the Kremlin, Assad told Putin: "First of all I wanted to express my huge gratitude to the whole leadership of the Russian federation for the help they are giving Syria.

"If it was not for your actions and your decisions, the terrorism which is spreading in the region would have swallowed up a much greater area and spread over an even greater area."

Earlier this month, 22 people including staff and patients were killed by a US air strike on a Doctors Without Borders (MSF) hospital in Kunduz, Afghanistan. MSF has said that the targeting of the hospital does not indicate that it was a "mistake".