Israeli warplanes attacked three Palestinian bases in Lebanon, and the guerrillas retaliated by shelling northern Galilee, an Israeli Army spokesman said.
The resumption of hostilities jeopardized the 10-month-old cease-fire negotiated by the United States after heavy fighting between the Israelis and the guerrillas in mid-1981. It was the first Israeli air attack on Palestinian targets in Lebanon since an April 21 air raid on guerrilla sites that killed 25 Palestinians.
Military spokesmen quoted by Israel Radio said the attack was in retaliation for incidents they said violated the cease-fire -- including the mining of a road in south Lebanon in which an Israeli soldier was wounded, and a bomb in a Jerusalem bus that injured two children.
The deepest Israeli raid was apparently at a Palestinian camp at Damour, south of Beirut. Beirut radio said the Israeli planes were met with shoulder-launched antiaircraft missiles. One radio report said eight planes were involved.
A number of artillery and rocket shells were fired from guerrilla bases near Nabatiyeh in south Lebanon but caused no damage or casualties, the Israeli spokesman said. The guerrilla firing lasted only a few minutes.
Foreign news reports quoted guerrilla leaders in Beirut as saying they regarded the Israeli attack as a trick, meant to prompt Palestinian bombings in northern Israeli settlements and thus supply the Israelis with a justification for invading Lebanon in a sustained drive against guerrilla bases. According to the reports, the Israeli Army was massed along its northern border, ready to cross into Lebanon in a renewed effort to crush the guerrillas.