JERUSALEM (AP) -- Israeli rescue services Wednesday reported a "massive" cross-border rocket barrage by Palestinian militants from the Gaza Strip - hours after an Israeli air strike in the first major exchange of fire since a truce took effect in June.
The Israeli military said in a statement that at least 35 rockets were fired from the strip early Wednesday, but there was no immediate word of injuries or damage.
The militant group Hamas said it fired the rockets.
Israel launched an airstrike on Gaza earlier Wednesday after its troops fought a fierce gunbattle with Hamas militants who then fired mortars into southern Israel. The fighting killed six Palestinians and threatened to unravel the truce that had mostly quieted violence in the volatile territory.
The violence was sparked after the Israeli army said its forces uncovered a tunnel about 300 yards inside the central Gaza Strip that militants planned to use to abduct Israeli soldiers. It said a special army unit headed to the area to destroy the tunnel.
The army said its operation did not violate the truce, but was a legitimate move to remove an immediate threat to Israel from Gaza, which is controlled by the Islamic militant group Hamas.
Hamas also insisted it had not violated the truce and was acting to prevent an Israeli incursion.
Dr. Moaiya Hassanain, a Palestinian Health Ministry official, said heavy gunbattles erupted, killing one Palestinian and wounding three, including one woman. Residents identified the dead man as a Hamas militant.
The army said it launched an airstrike at the mortar launchers and identified hitting them. Medics confirmed that five militants were killed in that strike.
The rocket barrage, the airstrike and the armed confrontation that preceded them were the first of their kind since Israel and Hamas agreed to a truce in June. The only other fatality was in July, when Israeli troops shot and killed a teenage Palestinian militant along the border with the Gaza Strip. There has been sporadic mortar and rocket fire since, but nothing on the scale of Wednesday's salvo.
A senior military official said troops had discovered a tunnel that was about to be used to abduct an Israeli soldier. The official, who spoke on condition of anonymity because of the sensitive nature of the matter, said the tunnel was dug from inside a Gaza home, illustrating that Hamas was using civilians for cover.
"We don't have any intention of breaking the truce, we are working to isolate this threat," the official said, noting that some 60 mortars had been fired since the truce and Israel had chosen not to respond.
Israel and Palestinian militant groups reached the Egyptian-mediated cease-fire in June after months of indirect negotiations. The deal halted a deadly cycle of Palestinian rocket attacks and Israeli reprisals.
Sporadic rocket attacks on southern Israel have persisted, provoking Israel to close its crossings into the coastal strip of 1.4 million Palestinians and keep the blockade it imposed on the area after Hamas overran the territory a year ago more or less intact.
The truce does not extend to the West Bank, which is ruled by Palestinian President Mahmoud Abbas, Israel's partner in peacemaking.
Taher Nunu, a Hamas government spokesman, said Hamas considered the Israeli airstrike a violation of the truce.
"This is a serious breach of the truce understandings reached through Egyptian mediation," he said in an e-mail message to reporters. "We consider this the most serious in a string of breaches."
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