Soldiers of the breakaway Caucasian republic of Chechnya refused to surrender despite running out of ammunition today, but the lapse in rebel shelling allowed Russian jets a free corridor to bomb the Chechen capital, Grozny. But, the Kremlin -- which faces mounting domestic opposition to the attacks -- today admitted that the fighting had gone on longer than Russian officials anticipated, although they attributed the delays to efforts to limit civilian casualties. (Several international military analysts said Russian troops' lack of battle-readiness was the real reason.) There was also no sign Russia was nearing its goal of encircling Grozny with troops and armor. Still, Russian President Boris Yeltsin, in a message broadcast to the Chechen people, called on rebels to give up and vowed that Chechnya "will once again become a full-fledged region of the Russian Federation."