Artillery fire rippled across the Chechen capital of Grozny early Tuesday, the day a limited cease-fire between Russia and Chechnya was to have taken effect.
There also were reports of Chechen missile attacks on Russian tanks southwest of Grozny.
Despite an uncertain start to the cease-fire, peace talks were to resume today in Sleptsovsk in the neighboring republic of Ingushetia, officials said.
The limited truce to stop the use of heavy artillery was reached Monday in talks between Col. Gen. Anatoly Kulikov, commander of Russian troops in Chechnya, and the chief of separatist Chechen forces, Aslan Maskhadov.
Both sides also agreed to work out an exchange of prisoners and the dead.
But previous agreements have failed to end the battles in this mountainous region 1,000 miles south of Moscow, and many on both sides were skeptical about this one.