Ukrainian troops clash with pro

Ukrainian troops have fought pitched gun battles with a pro- Russia militia occupying an eastern city - an apparent escalation of their efforts to bring the region back under government control.

Associated Press reporters heard gunfire and multiple explosions in and around Slavyansk, a city of 125,000 people that has become the focus of the armed insurgency against the new interim government in Kiev.

The Ukrainian interior minister, Arsen Avakov, said on his agency's website that pro-Russia forces were deploying large-calibre weapons and mortars in the region and that there were injured on both sides.

Government troops were facing about 800 insurgents, he said.

A pro-Russia militia spokesman in Slavyansk said an unspecified number of people had been killed and wounded in the clashes, including a 20-year-old woman killed by a stray bullet.

Both sides indicated fighting was taking place at several sites around the city.

An AP crew saw at least four ambulances rushing injured people to a city hospital. At least one militiaman was seen being carried in for medical treatment.

Ukraine is facing its worst crisis in decades as the polarised nation of 46 million tries to decide whether to look towards Europe, as its western regions want to do, or improve ties with Russia, which is favoured by the many Russian-speakers in the east.

In the last few weeks, anti-government forces have stormed and seized government buildings and police stations in a dozen eastern Ukrainian cities. Authorities in Kiev - who blame Russia for backing the insurgents - have up to now been largely powerless to react.

And since Russia has kept tens of thousands of troops along Ukraine's eastern border - and annexed its key Black Sea peninsula of Crimea last month - Ukraine's central government fears Russia could try to invade and grab more territory.

Since the government began trying to take back the buildings late last week, Slavyansk has been under a tight security cordon. Movement in and out of the city has ground almost to a halt, causing shortages in basic supplies. Lines have been seen at grocery stores.

The goals of the insurgency are ostensibly geared towards pushing for broader powers of autonomy for the region, but some insurgents favour separatism, and the annexation of Crimea looms over the entire political and military discussion.

Russia, which the international community has accused of promoting the unrest, has vociferously condemned Ukraine's security operations in the east.