Soldier, Civilian Killed in Fierce Ukrainian Clashes

Two people were killed in another round of intense shelling between Western-backed Ukrainian government forces and pro-Russian fighters in the separatist east, officials from both sides said on Friday.

Ukraine's military spokesman Andriy Lysenko said one soldier was killed and six wounded in the past 24 hours of fighting across the mostly Russian-speaking war zone.

Senior rebel commander Eduard Basurin accused Ukraine's army of killing a civilian in an overnight shelling attack on rebel-held Gorlivka, a town 25 kilometers (15 miles) northeast of the insurgents' de facto capital Donetsk.

Ukraine's army on Thursday reported the heaviest exchanges of tank and rocket fire since the two sides signed a February truce deal that has been repeatedly broken since.

Kiev's pro-Western forces this week have been fighting the militias for control of a strategic highway linking the government-held southeastern port of Mariupol with Donetsk, which sits to the north.

Most of the road is currently overseen by pro-Kiev units. But its capture could potentially allow the militias to step up their stop-start campaign to capture Mariupol -- a port city of nearly half a million that is on the western edge of the loosely-defined demilitarization zone.

The industrial port exports most of the east's factory output and provides a land bridge between rebel territories and the Russian-occupied Crimea peninsula.

Russia denies any links to the insurgents and officially provides them only with political backing at negotiations and U.N. Security Council forums.

But Ukraine's Western allies accuse the Kremlin of orchestrating and arming the uprising in revenge for Kiev's decision to pull out of Moscow's orbit and hitch its future to the European Union.

U.S. Secretary of State John Kerry called his Russian counterpart Sergei Lavrov on Thursday to express "grave concern" about the increased number of separatist attacks recently.

Ukrainian National Security and Defense Council Secretary Oleksandr Turchynov warned on Friday that Kiev "will be forced to introduce martial law and mobilize our country's entire potential... if there is an active use of Russian troops" in the conflict zone.

The United Nations estimates the violence has killed more than 6,800 people since April 2014 and has driven at least 1.4 million from their homes.