European security watchdog OSCE said numerous anti-aircraft rounds were fired at one of its drones monitoring a shaky truce in eastern Ukraine, and the United States blamed pro-Russian rebels for Sunday's incident.
The unmanned aerial vehicle — deployed to help monitor the cease-fire between government forces and separatists — was not hit and it later landed safely, the Organization for Security and Cooperation in Europe, or OSCE, said Monday.
The incident occurred on the same day as the rebels elected a separatist leadership in eastern Ukraine in a vote which was denounced by Kiev and the West and further deepened a standoff with Russia over the future of the former Soviet state.
It took place after the drone, flying east of the town of Mariupol at a height of about 1,520 meters, spotted an armored personnel carrier at what appeared to be a checkpoint, the Vienna-based OSCE said in a statement.
The rounds were fired from an anti-aircraft gun on the back of a civilian truck parked about 150 meters away, the OSCE said.
The U.S. envoy to the 57-nation OSCE said that given the location of the incident, "it was clear that this was done by Russia-backed separatists."
In a statement, Ambassador Daniel Baer called on Russia "to use its influence with the separatists to allow (the monitoring mission) to fulfil its mandate."
There was no immediate comment from Russia or the rebels about the firing at the drones, part of an OSCE mission that was initially deployed in March under a mandate approved by the OSCE's 57 member states, including Russia.
More than 4,000 people have been killed in the six-month conflict. Ukraine and the West have accused Russia of sending weapons and soldiers to help the rebels, a charge Moscow denies.
A Sept. 5 cease-fire has brought an end to full-scale clashes, though sporadic shelling continues.
The OSCE deployed unarmed observers in March to help ease tension and foster dialogue. It started using drones last month and now has two in operation, though only one is used at any given time. Two more will arrive shortly, a spokesman said.