Russian troops say they've advanced into the centre of the Chechen capital, Grozny, in what they describe as a decisive stage in the battle for the city.

The military said they were gradually expanding the zone they already controlled.

The Chechens have confirmed there's fierce fighting on two fronts, with the Russians concentrating on taking a strategic bridge on a transit route used by the rebels.

Russian commanders said it could be another few days before Grozny was entirely under their control.

The latest advance was preceded by relentless air and artillery bombardment.

A delegation from the human rights body, the Council of Europe, has gone from Moscow to Dagestan on its way to Chechnya. The officials want to visit Russian-held areas of Chechnya, as well as neighbouring Dagestan and Ingushetia, where some two-hundred-thousand Chechens have fled.

From the newsroom of the BBC World Service