A fifth person has died as a result of an attack inside a Jerusalem synagogue on Tuesday, according to a CNN report. The attack happened after two cousins entered the synagogue during morning prayers before attacking with butcher knives and a gun, resulting in the death of four rabbis and a policeman.

A further eight people were injured, including three who were seriously hurt before both assailants were shot dead by police at the scene, according to the foreign ministry.

Israeli Prime Minister Benjamin Netanyahu called for the nation to pull together against “those human animals who committed this massacre," while singling out the Islamic movement and the Palestinian Authority, who he claims "disseminate libels against the state of Israel."

"There are those who wish to uproot us from the capital, from our land," he said, referring to Jerusalem. "They will not be successful. ... We have to unify forces."

Aside from the policeman, the dead included three dual U.S.-Israeli citizens and one British-Israeli citizen. Israeli police spokesmen Mickey Rosenfeld told CNN that he wasn’t sure if the dual-nationality citizens were targeted.

Photos taken inside the synagogue showed the scale of the violence, with bodies strewn across the floor along with blood-drenched books, prayer shawls and walls.

It was the deadliest terror attack in Jerusalem since eight seminary students were killed in March 2008.

British Foreign Secretary Philip Hammond, along with U.S. Ambassador to Israel Dan Shapiro condemned the killings, with Shapiro calling them "a barbaric new low in the sad and outrageous history of such attacks."

"Tragically, this is not the first loss of life that we have seen in recent months," said U.S. President Barack Obama. He condemned the attacks "in the strongest terms" and said they were "a tragedy" for both Israel and the United States. "Too many Israelis have died, too many Palestinians have died. And at this difficult time, I think it's important for both Palestinians and Israelis to work together to lower tensions and reject violence."