NEW DELHI, India -- Soviet forces bombed the city of Kandahar in southern Afghanistan last week, killing 300 civilians in apparent retaliation for raids by Islamic guerrillas, rebel sources said Tuesday.
In separate fighting, popular guerrilla leader Ahmad Shah Massoud launched his first major counterattack against government positions in the strategic Panjshir valley, the sources said.
Soviet soldiers, part of a force of 105,000 troops backing President Babrak Karmal, launched the bombing raid on Kandahar six days ago in apparent retaliation for attacks by Afghan insurgents last week.
The rebel raids killed 15 troops and destroyed two tanks and two army trucks, the sources said.
Details of the attack on Kandahar, 250 miles southwest of Kabul, were not available, but the sources said 300 civilians were killed.
Independent confirmation of the reports was not possible because Western reporters have rarely been allowed to travel in Afghanistan since the Soviet invasion in 1979.
Guerrillas loyal to Massoud, the strongest of the Islamic guerrillas fighting to topple the Marxist government, attacked the Soviet-built base at Bazarak about four days ago, rebels said.
The exact number of casualties in the battle was not known. The rebels said many Soviet helicopters carried away casualties, most of them Afghan government troops who had been manning the outpost.
Massoud and his men were driven from the 70-mile-long Panjshir north of Kabul by a Soviet-led assault in the valley last spring. Since then, the rebels had mounted only minor harassment operations.
Rebels led by Massoud turned back six previous Soviet assaults on the rugged valley, which the Islamic insurgents used as a base for attacks on a vital Soviet supply route.
Massoud attracted world attention by his effective leadership and success in fighting the Soviets. It was believed for a time he might have been killed in the Soviet spring offensive.
In other developments, a Western diplomat said the Soviets have launched a major offensive in the Logar valley, south of Kabul.
Afghan and Soviet troops from the southern city of Ghazni were seen heading north towards the valley and troops and helicopters from Kabul were spotted heading south to meet them, the source said.