 -- Israel is calling up reservist forces and warning of an escalation of its activities in the Gaza Strip as more rockets fired by Palestinian militants fall in southern Israel.

A meeting was held by Israel’s security cabinet today, the same day some 40 rockets and mortars were launched from Gaza, according an Israeli military spokesman.

The goal of the call-up of those troops - all affiliated with the Iron Dome anti-missile system - is to protect cities in southern Israel, said Lt. Col. Peter Lerner on a conference call today. The troops are holding a “defensive stance,” but could “take it one step up if required,” he said, declining to elaborate.

Israel accuses Hamas – which controls Gaza - of failing to prevent rocket attacks by Palestinian militants. Overnight, Israel carried out air strikes on Gaza that left at least seven Hamas militants dead, along with two others from another group. Hamas warned today that Israel would “pay a tremendous price.”

“The idea is to see a controlled escalation, a monitored one,” said military analyst Alon Ben-David. “What you’ll see is more aerial strikes, more frequent, and more higher value [Hamas] targets.”

“I expect either Hamas to be deterred now and cease fire immediately, or we’re going to see a semi-quiet conflict escalate into a major conflict,” he added.

The growing tension comes amid some of the worst clashes seen in Jerusalem in a decade following the murder of 16-year-old Muhammad Abu Khdeir, a resident of the eastern neighborhood of Shuafat who was abducted and burned alive last Wednesday.

On Sunday, six Jewish suspects were arrested, three of whom confessed to the crime on Monday, according to Israeli media. It confirmed the widespread belief that Abu Khdeir’s murder was in response to the killings of three Israeli teens whose bodies were found near the West Bank city of Hebron last Monday. Israel accuses Hamas of being behind the murders, which the group denies.

In the clashes that followed Abu Khdeir’s death, his cousin Tariq from Tampa, Fla., was brutally beaten by Israeli police. The assault was captured on video by a neighbor, showing one policeman sitting on the 15-year-old while another repeatedly stomps on his head before kneeling down to keep punching him.

“When they punched me the first couple times I was awake and then they punched me a little more and then I went unconscious,” Tariq Abu Khdeir told ABC News today, his face still swollen with black eyes and stitches in his lip.

Abu Khdeir denies the Israeli police claims that he was involved in the clashes, masked and attacking police officers. Israel’s ambassador to the U.S., Ron Dermer, told ABC News that Abu Khdeir had used Molotov cocktails against security forces.

“I did not throw any Molotovs and I did not throw any rocks,” he said, “I was just watching the protests.”

Abu Khdeir – in Jerusalem on vacation visiting family - was held without charges for three days before being released on Sunday, ordered to stay in his uncle’s home under house arrest and to post a 3,000 shekel (around $875) bail. He says he’s happy to be out, but disappointed he won’t be able to enjoy the rest of his holiday before his family return to Florida on July 16.

“I’m very angry,” he said, “I don’t know why they gave me a punishment for something I didn’t do.”