BEERSHEBA, Israel – Nearly simultaneous explosions destroyed two buses in southern Israel on Tuesday, killing at least 16 people and wounding 85 in the first terrorist attack inside Israel in five months.

Authorities warned that the death toll could rise much higher because of the severity of the blasts, which hollowed out both buses and sent dozens of wounded tumbling out of the burning vehicles.

The blasts – triggered by two suicide bombers – occurred just seconds apart around 3 p.m. as the commuter buses were about 100 yards from each other in one of the major intersections in Beersheba, a large industrial city which had until Tuesday been largely spared the wave of terror that has swept over Israel for the last four years.

“I was just driving down the road and all of a sudden there was this incredible sound – I didn’t know what to do,” said Riki Mesikah, 38, who is seven months pregnant and was driving her car right in front of the first bus that exploded. She was unharmed even though the bus rear-ended her car.

“People were falling out, dropping out of the side of the bus,” she said, as she stood looking at both wrecks an hour later. “They weren’t any walking wounded really.”

“Then came the second blast, maybe just 40 seconds later,” said Gil Cohen, who ran from his small food stand to help after the first blast and was nearly hurt in the second.

“In Beersheba, we’ve never had anything like this,” he said, looking at the bodies, his eyes filling with tears. “We thought we were safe, but we’re not. Nobody is immune from this in Israel. Never.”

The Palestinian militant group Hamas claimed responsibility for the attacks, calling them retaliation for the Israeli assassinations earlier this year of its spiritual leader, Sheik Ahmed Yassin, and his successor, Abdel Aziz Rantisi. Those killings took place shortly after the last attack inside Israel, a suicide bombing in the port city of Ashdod in March that killed 10 people.

The attack was the deadliest since a female suicide bomber killed 21 people nearly a year ago in the northern city of Haifa.

The second Intifada, or Palestinian uprising, was launched in late September 2001, after nearly a decade of peace efforts failed to provide Palestinians with an independent state, or Israelis with security from sporadic terrorist attacks. During four years of Palestinian-Israeli violence, nearly 500 people have been killed in 114 Palestinian suicide bombings.

By Tuesday evening, the twin attacks had already prompted what appeared to be a major military operation in Hebron, the West Bank city where the two bombers came from, according to Hamas.

The attacks are likely to have repercussions for the government of Prime Minister Ariel Sharon, which is pushing a controversial pullout of settlements from the Gaza Strip and building a massive security fence that will eventually stretch the length of Israel’s nearly 500-mile border with the occupied territories of the West Bank and Gaza Strip.

“Israel will continue fighting terror with all its might,” Sharon said Tuesday night, pledging to push forward with Israel’s planned withdrawal from Gaza. “This has no connection to disengagement,” Sharon added. The explosions came just hours after he presented his Likud Party with the most detailed timetable yet for the pullout.

The debate over the fence, meanwhile, is also likely to intensify. Most of the construction of this massive barricade, which includes huge walls, trenches and electrified fences, has been around Jerusalem and central Israel, the entry point for many bombers over the last four years.

The southern part of the country, where Beersheba is located, has been left open, which exposed the city to the volatile Palestinian city of Hebron, just 28 miles away.

In Hebron, Hamas distributed a leaflet claiming responsibility for Tuesday’s attack, but did not name the bombers.

“If you thought that the martyrdom of our leaders would weaken our missions and discourage us from Jihad, then you are dreaming,” the statement said.