Libya NTC forces surround pro-Gaddafi fighters in Sirte

Columns of smoke rose above the city as government forces fought their way in, street by street, until they reached the Ouagadougou conference centre where pro-Gaddafi loyalists are holed up.

At least 12 people were killed and more than 190 injured, doctors said.

Thousands of civilians have left Sirte but many have remained behind.

The two sides battered each other with mortar shells, rockets and tank fire in what transitional government forces have described as the final assault on Sirte, some 360km (225 miles) east of the capital, Tripoli.

The battle for Sirte comes nearly two months after the former rebels seized control of virtually all of Libya, ousting former leader Col Muammar Gaddafi.

The BBC's Jonathan Head in Sirte says Libya has been unable to think about the future until the city falls.

Two-pronged assault

Troops loyal to the National Transitional Council (NTC) converged on Sirte from Misrata in the west and Benghazi in the east.

They faced heavy resistance from pro-Gaddafi snipers and forces as they advanced towards the city centre.

The Ouagadougou conference centre, where many of the Gaddafi loyalists are believed to have barricaded themselves, has become the focus of the fighting.

There was sustained fire from mortars, machine guns and snipers around the centre, holding off NTC forces.

"We entered the Ouagadougou centre compound but fell back because of RPG [rocket-propelled grenade] and sniper fire. There's no cover there," NTC fighter Faisal Asker told the AFP news agency; Kazinform cites BBC.

To learn more go to www.bbc.co.uk