Barak has warned that Israel won’t hesitate to invade Gaza, saying his country can’t tolerate rocket fire into its southern and central cities.

Officials said the exact objectives and targets of an expanded operation in Gaza were still unclear. On Israel’s Channel 2 television, Barak said Israeli troops “will need to go house to house, and then we will need the lessons of the past," a reference to previous Israeli military campaigns in Gaza and Lebanon.

Israeli defense analysts said troops most likely would focus on weapons caches and known Hamas artillery sites. A Fajr rocket is about 30 feet long and is launched from a truck-like mobile platform. Israeli intelligence officials have said they think that many of the rockets have been hidden underground.

Gil Chernosky, a reserve soldier from Tel Aviv, told McClatchy that deterrence was the only recognizable goal in Gaza.

Chernosky, who fought in Gaza during Operation Cast Lead, a massive Israeli operation there four years ago, said, “I hope this time will be different. I hope that this time, after we go into (Gaza) we will have a few more years of quiet in the south of Israel.”

He complained that during Operation Cast Lead, Israel was stopped from “finishing what it needed” to do in Gaza because of international pressure. More than 1,300 Palestinians had been killed by the time the operation ended after three weeks.

“We stopped before we were done, and now Palestinians are again firing rockets at our houses,” he said.

Chernosky said he wasn’t surprised that rockets had managed to strike deep into central Israel.

“It was a matter of time before the center woke up and realized they weren’t safe,” he said.

In Tel Aviv, residents who’d shrugged off two rockets that landed Thursday as a lucky strike were less taciturn Friday as it became clear that the city was no longer invulnerable to attack.

“We’ve always felt apart here, like the crazy stuff happening in the Middle East wasn’t a part of our lives. You know, like it couldn’t touch us,” said Davey Cohen, a 22-year-old student. “Now I have to figure out where my bomb shelter is.”

Advertisements on Israeli state TV and radio stations told residents in the country’s center where to find secure areas in the event of a rocket attack.

Across Tel Aviv, residents could be seen clearing out old furniture and boxes from bomb shelters that had become storage units.