A 76-year-old professor who survived the Holocaust was shot to death while saving his students from the Virginia Tech assailant, students said.

Liviu Librescu, an internationally respected aeronautics engineer who taught at Virginia Tech for 20 years, saved the lives of several students by barricading his classroom door before he was gunned down in the massacre, according to e-mail accounts sent by students to his wife.

"My father blocked the doorway with his body and asked the students to flee," his son, Joe Librescu, said in a telephone interview from his home outside of Tel Aviv. "Students started opening windows and jumping out."

The gunman, identified as 23-year-old Cho Seung-Hui, an English major and native of South Korea, killed 32 people before committing suicide, officials said, in what was the deadliest shooting rampage in modern U.S. history.

On campus, students spoke of Librescu's bravery.

"He should be recognized as a hero," Virginia Tech graduate student Philip Huffstetler said. "We should be in such great debt to his family for the rest of our lives."

"He is the reason that the student could not get inside and shoot more people," said Asal Arad, a Virginia Tech student. "Obviously, he is a hero."

Librescu had known hardship since childhood.

When Romania joined forces with Nazi Germany in World War II, he was first interned in a labor camp in Transnistria and then deported along with his family and thousands of other Jews to a central ghetto in the city of Focsani, his son said. According to a report compiled by the Romanian government in 2004, between 280,000 and 380,000 Jews were killed by Romania's Nazi-allied regime during the war.

As a successful engineer under the postwar Communist government, Librescu found work at Romania's aerospace agency. But his career was stymied in the 1970s because he refused to swear allegiance to the regime, his son said, and he was later fired when he requested permission to move to Israel.

After years of government refusal, according to his son, Israeli Prime Minister Menachem Begin personally intervened to get the family an emigration permit. They moved to Israel in 1978.

Librescu left Israel for Virginia in 1985 for a sabbatical year, but eventually made the move permanent, said Joe Librescu, who himself studied at Virginia Tech from 1989 to 1994.

In Romania, the academic community mourned Librescu's death.

"It is a great loss," said Ecaterina Andronescu, rector of the Polytechnic University in Bucharest, where Librescu graduated in 1953. "We have immense consideration for the way he reacted and defended his students with his life."

At the Polytechnic University, where Librescu received an honorary degree in 2000, his picture was placed on a table, a candle was lit, and people lay flowers nearby.

"We remember him as a great specialist in aeronautics. He left behind hundreds of prestigious papers," said one of the professors, Nicolae Serban Tomescu.

Librescu published extensively and received numerous awards for his work.

"His work was his life in a sense," Joe Librescu said.

The Associated Press contributed to this report.