BBC News with Marion Marshall

Witnesses have told the BBC that Libyan troops have opened fire with machine guns and larger-calibre weapons on anti-government protesters in the city of Benghazi, killing a number of people.

They described scenes of chaos as snipers shot from the roofs of buildings and protesters fought back against troops on the ground. Jon Leyne has more details.

Witnesses in Benghazi are describing what sounds like a sustained battle with government forces. According to some accounts which are impossible to

verify

, a major

barrack

s or security headquarters has fallen to the opposition. There are also reports on the Internet that a nephew of Colonel Gaddafi has been killed in the fighting. Earlier, witnesses described how a unit of elite government forces, many of them apparently from outside Libya, were sent in to Benghazi. The troops have been using gunfire and even mortars against the opposition.

Substantial

numbers of casualties have been received at local hospitals, though figures are hard to verify.

Protesters in Bahrain have streamed back into Pearl Square in the capital Manama to continue their demonstrations against the government. They were

initial

ly confronted by riot police who opened fire with tear gas and shotguns, but the police then

pulled back

and left. Caroline Hawley sent this report from Pearl Square.

There are now families with flowers, flags and balloons where this morning there were tanks. In the middle of the day, the crown prince ordered the military off the streets. For a short while, police in riot gear kept the protesters out, but then they suddenly