6 killed in east Ukraine fighting

Four pro-Russian rebels, a Ukrainian soldier and one civilian were killed in clashes that broke out over the past 24 hours in violation of a February truce deal, officials said Tuesday.

The civilian died during an artillery fire attack on the Avdiivka Coke and Chemical Plant, which sits on the outskirts of the rebels' de facto capital Donetsk.

A resulting fire at the plant caused a small ammonia leak, Ukraine military spokesman Andriy Lysenko told reporters, without providing further details.

Lysenko said 12 Ukrainian soldiers were also wounded in clashes across the war zone.

The pro-Kiev governor of the separatist province of Lugansk said a soldier died when his military ambulance came under fire near the Russian border. It was not clear whether he was referring to the same serviceman as the one mentioned in Lysenko's daily update.

Rebel authorities said four of their fighters were killed and another three injured in the past day.

Fighting was particularly heavy in Shyrokyne, near the strategic port city of Mariupol, military officials from both sides said.

The 13-month war, sparked by the separatists' rejection of the pro-Western leadership in Kiev, has claimed nearly 6,300 lives and left well over a million people homeless.