As Russian President
Rebels attacked positions of Ukraine's national guard near Slovyansk with mortar fire Friday, according to a statement posted on the national guard's website.
"The terrorists set up a 120-mm mortar complex on the territory with which they began to render active strikes on Ukraine's law-enforcement check point," the statement read. "Resulting from the mortar fire there were dead and wounded among the law-enforcement officers."
There also were reports by eyewitnesses of a Ukraine air force An-30 plane being shot down over Slovyansk, in the embattled Donetsk region, on Wednesday, UNIAN news agency reported.
On Friday at a D-day commemoration in Normandy, France, Putin and Poroshenko met for the first time after Poroshenko's recent election and reportedly expressed readiness to find a peaceful resolution to the violence.
"During their brief conversation, both Putin and Poroshenko spoke in favor of stopping the bloodshed in southeastern Ukraine as soon as possible, as well as about [the need] for both sides – the Ukrainian military forces and Ukrainian federalization supporters – to cease hostilities," Russian presidential spokesman Dmitry Peskov said.
"Moreover, it was confirmed that there was no alternative than to settle the situation through peaceful political means," he added.
Dozens of Ukraine army servicemen, security and police officers have been killed and injured in fighting in the break-away Luhansk and Donetsk regions, officials recently said. About 200 have been held as prisoners or hostages by pro-Russia gunmen in the Donetsk region alone, regional governor Sergei Taruta said.
"Today negotiations are being conducted aimed at freeing over 200 hostages, citizens of different countries held by the militants," Taruta said in an interview to Ostrov, a local news agency.
A rebel field commander, a Russian national code-named Bes, or Devil in Russian, threatened to start killing hostages in a mock-execution video posted on YouTube if authorities didn't exchange one of his agents they are holding for the hostages in his custody.
In April, Ukraine's Security Service identified Bes as Igor Bezler, a former Russian military intelligence officer.
Despite the continued hostilities, some analysts hailed the two leaders' contact as a positive sign.