Heavy fighting has been reported in Russia's breakaway region of Chechnya. Chechen rebels say they launched attacks against Russian forces in response to an ultimatum made by Russian President Vladimir Putin.

Chechen fighters launched a series of attacks against Russian troops in several towns in southern Chechnya.

In the large town of Shali, the Chechens fired at an administration building and a military command post. Fighters reportedly seized several roads, and each side has suffered many casualties.

Chechen spokesman Mavlodi Udugov told news agencies by satellite phone the attacks are the rebel's answer to President Putin's demand last week that they lay down their arms.

Mr. Putin had delivered an ultimatum, giving the Chechens 72 hours to begin discussing disarmament with Moscow.

There was some contact with some low-level officials, but the rebels rejected any talk of handing in their weapons without political negotiations to resolve what they call their fight for independence.

Mr. Putin has long accused the Chechen of having links with alleged international terrorists, including Osama bin Laden. Mr. bin Laden is the prime suspect in the recent attacks against the United States.

At least one senior Chechen field commander is from the Middle East, and reportedly has links with Mr. Bin Laden.

But Chechnya's president, Aslan Maskhadov, says the Kremlin is deflecting attention from the independence issue by saying that all Chechen fighters are terrorists.

Nonetheless, Mr. Putin has made diplomatic gains with Western leaders on the Chechen issue after the Kremlin announced its support for the war against terrorism.

European leaders toned down their criticism of alleged human rights abuses by Russian troops in Chechnya after they met with Mr. Putin in Germany last week.

Russia is sharing intelligence information about terrorist groups in Afghanistan with the United States and has offered to open its airspace to foreign planes if necessary.