7 Ukrainian troops killed in overnight fighting

June 18, 2014: In this file photo, a pro-Russian fighter holds a gun during a handover of the bodies of Ukrainian troops killed in a plane shot down near Luhansk, at a checkpoint in the village of Karlivka near Donetsk, eastern Ukraine. (AP)

YANAKIYEVE, Ukraine – Seven Ukrainian troops were killed in overnight fighting in the restive east, Ukrainian officials said Friday, as clashes between government forces and pro-Russian rebels continued two days after President Petro Poroshenko said he would soon call a unilateral cease-fire.

Rebels were operating tanks in the region, a sore spot between Russia and Ukraine, which accuses Russia of letting the vehicles cross the border.

Vladislav Seleznev, spokesman for Ukrainian forces in the east, said seven soldiers were killed and 30 injured in fighting against pro-Russian separatists outside the village of Yampil in the Donetsk region since Thursday. Seleznev said 300 rebels were killed, but that could not be immediately verified.

Pro-Russian fighters were moving in a column with two tanks and three armored personnel carriers near the town of Yanakiyeve in the direction of the town of Horlikva in the Donetsk region. The tanks flew small flags of a pro-Russian militia but otherwise had no markings. The fighters declined to say what they were doing, other than that it was a "secret operation."

Russian President Vladimir Putin has voiced concern about the Ukrainian military onslaught, while NATO on Thursday reported that Russia was resuming a military build-up at the Ukrainian border.

Putin and Poroshenko discussed details of the peace plan in a telephone call on Thursday. Poroshenko's office said he emphasized the need for introducing effective border controls and quickly releasing hostages.

Late on Thursday, Putin chaired a meeting of Russia's Security Council, a body that includes the country's top officials, to discuss the crisis in Ukraine, the Kremlin said on Friday, but stopped short of providing details.

The U.N. says at least 356 people, including 257 civilians, have been killed since May 7 in eastern Ukraine.