At least 11 Americans have died in bloody violence in Israel, President Joe Biden said on the third day since Palestinian militants launched a stunning and complex surprise attack in Israel.

In a statement, Mr Biden described the deaths as the “heart-wrenching” results of an “appalling terrorist assault against Israel.”

He said the U.S. believed that the Hamas militant group was likely holding American citizens as prisoners. He added that the U.S. is working with Israel to handle the hostage crisis.

“This is not some distant tragedy,” the president said in his statement. “The ties between Israel and the United States run deep. It is personal for so many American families who are feeling the pain of this attack,” the president added.

The identities of the dead Americans were not immediately released, and it was unclear if any were from New York, home to about 1.6 million Jews.

In New York City, there was a heavy police presence at synagogues on Monday.

Major U.S. airlines have cancelled flights into and out of Israel.

According to a count by Rep Grace Meng’s office, at least 50 New York residents were seeking to return from Israel on Monday.

The State Department said it was in contact with the families of the dead Americans.

More than 1,300 people have already been reported dead in the conflict, escalating Monday as Israel ordered an intense retaliatory assault on the blockaded Gaza Strip.

According to the Israel Defence Forces, at least 700 people have died in Israel.

The Palestinian death toll was 687, the Palestinian Health Ministry said Monday.

Ms Meng, a Democrat representing much of central and eastern Queens, wrote a letter to the State Department asking it to “use all resources at its disposal” to help Americans in Israel return to the U.S.

A spokesman for Ms Meng, Jordan Goldes, said a “handful” of Ms Meng’s constituents were in Israel.

Senate Majority Leader Chuck Schumer, a Brooklyn Democrat, said in a statement late Sunday night that he had been briefed on the rising American death tally – then four – and that it would rise.

“The viciousness and brutality of this unprecedented attack from Hamas targeting innocent civilians – children, families, seniors – is overwhelming and heart-wrenching,” added Mr Schumer, who is Jewish and is currently on a trip to China.

Mr Schumer met with China’s President Xi Jinping on Monday and urged China to stand with the U.S. in a united front supporting Israel, Mr Schumer’s office said.

Mr Schumer’s spokesman, Angelo Roefaro, said the majority leader convinced Xi to strengthen a statement opposing violence against civilians in Israel.

(dpa/NAN)