HAIFA, Israel – On the first hour of the first day of the Jewish working week, 30 railwaymen were starting train repairs in the northern city of Haifa when a missile crashed through the ceiling.

The corrugated plastic roofing of the Israel Railway’s maintenance hangar in which they were working provided scant protection against the rocket, fired by Hezbollah militants 20 miles north across the Lebanese border yesterday.

Pools of blood and twisted commuter carriages on the rails bore testimony to the new reality that Haifa is now on the front line in Israel’s growing conflict with its northern neighbor.

“When I entered the depot, the roof was still on fire from the rocket that landed on it,” a fireman, Hezi Levy, said. “Then I saw the bodies of the six people who were killed lying next to each other. Another employee came running towards me, tried to speak, then collapsed and died.”

Police were quick to establish a cordon around the area, but it was not enough to hide the scale of the damage. Rivulets of water used to put out the blaze were tinted red.

The trains, in for minor repairs, had shattered windows and deep shrapnel gouges.

“It was a really big bomb,” a railway worker said, describing the explosion while fielding calls on his cell phone from worried friends and relatives.” It’s just awful. My friends have been killed.”

By last night the death toll had reached eight, with 20 others wounded, six seriously, prompting vows of an unflinching counterstrike from Prime Minister Olmert and the defense minister, Amir Peretz.

As Mr. Olmert said the attack on Haifa would have “far-reaching consequences for our relations on the northern border and in general,” speculation grew that Israel’s retaliation would include an imminent ground offensive into southern Lebanon.

Many of Haifa’s 300,000 residents were not waiting to find out whether Israel would send its armored and infantry divisions north across the Lebanese border.

Shortly after the attack, a very different, civilian, motorized column was making its way slowly south down the coastal Route 2.

Traffic was thick as those who only a few days ago vowed to stay packed their bags, got into their cars, and left. Outside hotels, queues of people waited for buses and taxis to evacuate them.

“We’ve had a lot of people check out,” the manager of one major chain said.

For those who remained, however, the Israeli authorities promised at least a minute’s warning before every fresh attack, with sirens heralding the latest barrage.

“People can leave if they want but our advice has been to stay close to shelter and listen for the sirens,” a police spokesman, Micky Rosenfeld, said outside the stricken railway yard.

Minutes later those sirens did sound, and Mr.Rosenfeld, security officials, investigators, and journalists dropped everything and sprinted for cover to panicked cries of “Move! Run!”

At Haifa’s university and technology institute, students left their desks in the middle of final exams and ran, with their supervisors, to bomb shelters.

“From the moment the rocket barrages fell, an order was received to immediately halt all exams and to gather everyone,” a university spokesman, Amit Gilat, said. “Everyone is in the shelters.”

Every neighborhood in the city has a communal shelter, but most are empty as people take refuge in basements or in strong rooms in their apartments, which have been obligatory in buildings constructed after 1992.

“We have a sheltered room, reinforced with concrete, without any windows,” Ron Kermon, 48, said.” It is standard in new buildings.”

He added that his 37-year-old wife, Yafit, and 15-year-old son, Dror, had sheltered there during the day while he had taken cover at the printing shop where he works.

“One shell hit close by and I felt the blast as it landed,” he said. “But I have some military background and did not feel too scared. You can’t panic.”