Americans Killed at Synagogue Include Grandson of Prominent Boston Rabbi, Kansas City Native Five people were killed after an attack on an Israeli synagogue.

 -- Three Americans were among five killed after a brutal synagogue attack in Jerusalem today -- including a Kansas City-born rabbi and the grandson of a prominent American Jewish leader.

Two Palestinians armed with knives and a gun ran into the synagogue and attacked worshipers during morning prayers.

The Americans were all dual American-Israeli citizens, according to The Associated Press. The fourth victim was a British national, according to the Israeli government.

Kalman Levine, also called Cary William Levine, originally from Kansas City, Missouri, was among the Americans killed.

Levine devoted himself to religious study after moving to Israel, according to the Israel Ministry of Foreign Affairs.

His son, Rabbi Yerachmiel Levine, eulogized his father by recounting how he would read the Torah all day.

"My father would study [Torah] all day long and would return home at night only to learn some more until he would fall asleep in his chair," Yerachmiel Levine said, according to the Israel Ministry of Foreign Affairs. "Abba [Father], you were in the middle of saying the Shema [prayer] when your soul left your body and the terrorists came and murdered you."

Levine's former brother-in-law, Shimon Kraft, said Levine moved to Israel in 1982 and "never came back."

"It's a rough day for all of us," said Kraft, now based in Los Angeles. "The Kansas City Jewish community is a small one."

Kraft said he knew Levine, 55, since they were 7 years old and both in the first class of a Hebrew day school in 1966.

Kraft said Levine lived in a "safe neighborhood" and had not talked about being worried for his safety.

"He got killed in the same place he prayed every day for years," said Kraft. "When you live there, you don't think it's going to happen in your neighborhood."

According to Kraft, Levine had remarried since they were brother-in-laws and had nine children and five grandchildren.

Another attack victim, Rabbi Moshe Twersky, 59, immigrated to Israel from America in 1990, according to the Israel Ministry of Foreign Affairs.

He was the grandson of a prominent Boston rabbi Joesph Soloveichik and the son of Rabbi Isadore Twersky, the founder of Harvard's Center for Jewish Studies.

Twersky lived next door to the synagogue where he was killed and was married with five children, Israeli officials said. He was the dean of an English-language school for Jewish students called Yeshivas Toras Moshe, according to the school's website.

The third American victim was identified as Rabbi Aryeh Kupinsky, 43. According to the Israel Ministry of Foreign Affairs, Kupinsky worked in computers and regularly prayed at the synagogue where he was killed.

Kupinsky was married with five children aged 5 to 16, according to the Israel Ministry of Foreign Affairs.

The Associated Press, and ABC News' Luis Martinez and Alex Marquardt contributed to this report.

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