Israeli forces shot a Syrian soldier dead and captured another who infiltrated into the Israeli-occupied Golan Heights today in a rare flare-up across the normally quiet cease-fire line, the Israeli army said.

Syria, in turn, accused Israeli troops of firing on Syrian policemen and violating a cease-fire agreement that has held for nearly three decades, although Israel and Syria are technically still at war.

The Israeli army said its forces came under fire from a group of armed infiltrators who crossed from Syria into Israeli-ruled territory.

"The soldiers returned fire and killed one of the group. The second member of the group was captured and taken for questioning," the army said in a statement. "It was found they were Syrian soldiers who were dressed in civilian clothes."

Brig. Gen. Avi Mizrahi, commander of Israeli forces in the Golan Heights, said Syrian soldiers at a nearby military post across the border opened fire at Israeli troops during the clash but that Israeli forces did not return fire.

The army said the gunfire from Syria continued for an hour.

"It should be emphasized that at no time did the forces return fire into Syrian territory," the army said.

A Syrian military spokesman quoted by SANA, the state news agency, accused Israel of firing first.

"As three Syrian citizens . . . including two policemen in sports clothes, were heading for a stream at the junction of the Raqqad valley and the Yarmouk river to get drinking water, they were fired on from the Israeli side, leading to the martyrdom of one and the loss of another," SANA quoted the spokesman as saying.

A Syrian patrol returned fire, the spokesman said in describing the incident as a "violation of the disengagement agreement and an unjustified provocation."

Israeli military intelligence officials have warned in recent months that militant groups in Lebanon and Syria might try to open a second front and attack Israel if a brewing conflict between the United States and Iraq erupts into war.

But Israel played down the clash as an "isolated incident."

Israel captured the Golan Heights from Syria in the 1967 Middle East war. Peace negotiations over the strategic plateau, which became a battlefield again in 1973, deadlocked in January 2000.