SLAVYANSK, Ukraine — Pro-Moscow separatists controlling the east Ukrainian town of Slavyansk called for Russian peacekeepers to deploy and announced a curfew after a gun battle nearby that killed at least two of their militants.

Vyacheslav Ponomaryov, the rebel leader in the town, told reporters he had made an appeal to Russian President Vladimir Putin “to study the possibility of sending peacekeepers to defend the population against the fascists” — the term Moscow and the separatists use to designate Ukraine’s new government and its supporters.

He also announced a curfew for the town of 130,000 people, during which it would be forbidden to be out in the streets.

“The curfew comes into effect today — from midnight to 6:00 a.m.,” he said.

A car with a megaphone drove around Slavyansk’s streets repeating the order.

The steps came hours after a deadly gun battle at a road block in the village of Bilbasivka, 18 kilometers (11 miles) west of Slavyansk.

An AFP photographer there saw the bodies of two killed militants. But Ponomaryov said four people had died: three militants and one of the unidentified attackers.

Russia’s foreign ministry said Sunday it was “outraged” by the attack near Slavyansk, which it blamed on the Right Sector, a Kiev-based ultra-nationalist group that was at the vanguard of street protests that forced the February ouster of pro-Kremlin Ukrainian president Viktor Yanukovych.

The Right Sector has dismissed the charge as “lies” and “propaganda” designed to portray eastern Ukraine as ungovernable by Kiev.

A pro-Russian rebel who said he was at the roadblock near Slavyansk at the time of the attack told AFP: “Four cars pulled up to our roadblock around 1:00 a.m. We wanted to conduct a check, and then they opened fire on us with automatic weapons.”

The masked 20-year-old, who gave his name as Vladimir, said there were around 20 attackers, but he was not sure of casualties on their side.

Three of his fellow pro-Russian militants at the barricade were killed and four were wounded, he said.

“Reinforcements quickly arrived at our roadblock and the attackers left.”

Separatist gunmen maintain a firm grip over a string of towns across Ukraine’s industrial east despite an international deal demanding they vacate state buildings they are occupying.

The Western-backed authorities in Kiev had declared an Easter truce in their so far unsuccessful military operations to try to oust the separatists.

The gun battle was the first violence reported since a Geneva accord worked out between Russia, Ukraine, the United States and the European Union that is meant to see “illegal armed groups” lay down their weapons and cease their occupation of public buildings.

The separatists in Slavyansk and elsewhere in the east have refused to do so.