Updated

An Israeli police official told Fox News that Palestinians were celebrating the terrorist attack that left four dead in central Tel Aviv Wednesday night.

Israel Police Superintendent Micky Rosenfeld told “On the Record with Greta Van Susteren” that Israelis will mourn those killed at the Sarona market for the next week and vowed that further action would be taken.

“Unfortunately, within the West Bank area we have seen Palestinians celebrating this attack,” said Rosenfeld. “Meanwhile here in Israel ... we will be mourning for a week over the people that were lost -- and we are talking about four innocent people that were shot to death, literally shot and killed at close range for no reason whatsoever.”

The attack, one of the deadliest in an eight-month wave of violence, took place around 10 p.m. local time in an upscale area of cafes and restaurants near the central military headquarters and Defense Ministry compound. A Fox News producer in Jerusalem confirmed five others were wounded in the attack and in severe condition.

The two attackers were described to Fox News as Palestinian cousins from Yata in the Hebron area of the West Bank who were known to Israeli authorities. The gunmen disguised themselves as Orthodox Jews, a law enforcement source told Fox News.

Hamas, the Islamic militant group that rules Gaza, welcomed the attack and claimed the shooters as members of the organization. Hamas official Mushir al-Masri called the shootings a "heroic operation" and the group later issued an official statement promising the "Zionists" more "surprises" during the Muslim holy month of Ramadan.

The Times of Israel reported that Fatah, Hamas' rival, issued a statement on Twitter saying Israel was "reaping the repercussions of choosing violence against the Palestinian people."

The Israeli newspaper Haaretz, citing Palestinian media, reported early Thursday that Israeli military forces had surrounded Yatta and were preparing to carry out arrests and interrogate family members of the attacks.

"Whatever action has to be taken will be taken based on the security assessments that will be carried out and implemented both tonight as well as tomorrow morning,” Rosenfeld told "On The Record."

Rosenfeld told Fox News that one of the suspects was shot by police and the other was captured by authorities. He said the suspect wounded by police is in moderate condition at a nearby hospital.

The weapons used by the attackers included a “Karl Gustav improvised machine gun,” Israeli police told Fox News. Haaretz reported that the assailants had no prior criminal record and had entered Israel illegally.

Prime Minister Benjamin Netanyahu met with his defense minister and security leaders shortly after the attack and then traveled to the scene. He called the attack a "cold blooded murder by despicable terrorists," according to a statement from his office.

Meital Sassi told Channel 10 TV she was out with her family celebrating her son's birthday when she heard shots and "immediately understood it was a terror attack."

"We ran like lighting with the baby and the stroller.... I yelled at people who didn't understand what was happening to run," she said.

Tel Aviv district police chief Moshe Edri told Haaretz there was no prior terror alert before the shooting took place.

The Ynet news website showed CCTV footage of civilians running into a nearby restaurant to take cover.

Shlomi Hajaj, director of the market, told Channel 10 that security guards at the entrance "prevented the attackers from entering the facility, averting a bigger disaster as the compound was packed with people."

Channel 10 cited witnesses as saying the two attackers were dressed in suits and ties and spent time in a nearby restaurant, sitting at the bar, before the attack. It showed footage of police forensic teams dressed in white suits examining items in restaurants at the scene.

U.S. State Department spokesman Mark Toner condemned the "horrific terrorist attack" in a statement, saying "cowardly attacks against innocent civilians can never be justified."

Israel has been struggling to cope with eight months of Palestinian attacks that have killed 28 Israelis and two Americans. About 200 Palestinians have been killed during that time, most identified as attackers by Israel.

Most of the attacks have been in east Jerusalem or the West Bank, territories Israel seized from Jordan in the 1967 war which the Palestinians want for their future state.

But Tel Aviv, Israel's most cosmopolitan city, has not been spared.

A member of Israel's Arab minority went on a shooting rampage on New Year's Day, killing three people. And in March a Palestinian went on stabbing spree, killing an American and wounding 7 other people before he was shot and killed.

Fox News' Jennifer Griffin and The Associated Press contributed to this report.