More than 60 Syrian soldiers have been reported killed in US-led coalition air strikes near a military base as they battled Islamic State of Iraq and the Levant fighters, a Russian military spokesman said.
Major-General Igor Konashenkov said the air strikes on Saturday took place near the Deir Az Zor airport in eastern Syria and were carried out by two F-16s and two A-10s. He did not identify the planes' country affiliation, but said they were part of the international coalition.
Konashenkov said Syrian authorities told the Russians that 62 soldiers were killed and more than 100 wounded.
The Russian Defence Ministry said the planes had bombed Syrian troops battling ISIL near the airport. Fierce fighting between the Syrian army and ISIL fighters was now under way.
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The ministry said the strikes had been carried out between 5pm-5:50pm local time by jets that had entered Syrian airspace from the direction of Iraq.
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"If this air strike was the result of a targeting error, it is a direct consequence of the US side's stubborn unwillingness to coordinate its action against terrorist groups on Syrian territory with Russia," the defence ministry said in a statement.
Moscow called for an emergency meeting of the UN Security Council to discuss the deadly air strikes.
Citing the Deir Az Zor airport, the Syrian Observatory for Human Rights said at least 80 Syrian soldiers died.
American officials acknowledged that the US-led coalition fighting ISIL in Syria may have hit Syrian military positions.
"Coalition forces believed they were striking a Daesh fighting position," a Pentagon statement said, using an Arabic acronym for the group.
"The coalition air strike was halted immediately when coalition officials were informed by Russian officials that it was possible the personnel and vehicles targeted were part of the Syrian military."
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Al Jazeera's senior political analyst Marwan Bishara said Moscow used the incident to hit home the importance of communication between Russia and the US in military operations in Syria.
"What the Russians are saying today is you - the Americans - because you don't want to coordinate on the ground these sorts of mistakes are going to happen more often. It's quite foggy in terms of coordination on the ground. With the various violations of the ceasefire, you're going to see more friendly type fire going on," Bishara said.
Russia and the United States brokered a ceasefire in Syria that took effect on Monday and has largely held despite dozens of alleged violations.
Russia is a key ally of Syrian President Bashar al-Assad's government and has been carrying out air strikes on behalf of his forces since last year.
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Source: Al Jazeera And Agencies