United Nations officials say nearly 10,000 people have crossed into Ingushetia in the past four days, the biggest exodus for some time.

A BBC correspondent in Ingushetia says refugees from Grozny have brought with them tales of horror. Some describe watching friends and relatives die beside them whilst trapped in cellars under constant Russian bombardment.

The UN says those who reach Ingushetia face the threat of disease, especially tuberculosis.

At least 20,000 civilians are thought to be trapped in the city, many of them old and infirm and living in terrible conditions in underground shelters.

Rebel resistance

The Russians are having limited success in their bid to capture the city, which began a month ago, before being briefly suspended.

Federal forces have suffered heavy losses in the assault on Grozny.

Senior officials quoted by the Russian Interfax agency say that 1,173 soldiers have been killed since fighting began in September.

But independent sources such as a soldiers' mothers organisation say around 3,000 servicemen have lost their lives.

Chechen rebels say they are holding off the Russian forces about 500m from the capital's strategically important Minutka square.

Click here for a map of Grozny

The Chechens are defending the square from tall buildings and underground passages, as federal troops attack from the Oktyabrskiy district, Interfax reported, quoting Chechen rebel headquarters.

The Chechen commander in Grozny, Aslanbek Izmailov, said small bands of rebels had stopped trying to hold territory and were launching hit and run attacks on the Russians, striking from the rear.

The Russian military claims to have most of Grozny under control, but troops which have taken streets by daylight have been forced to abandon them at night for fear of rebel ambushes.

Chechen sources say they have killed 150 Russians in the capital over the past two days, while Russia says it has killed more than 100 rebels since Monday.

The Chechens admitted 15 casualties, while the Russians said they had lost only six men.

Southern offensive

Russian aircraft are continuing to bomb strategic gorges in rebel-held areas to the south.

The Russians have been trying to dislodge rebels from woods in the lower Argun and Vedeno gorges for two weeks.

Interfax reported that Russian bombers, attack aircraft and helicopter gunships had flown more than 250 combat missions in Chechnya, despite poor weather conditions, on Monday.

North Caucasus command claimed 30 rebel strongholds had been destroyed.

Click here to return