A pregnant young woman who was feeling ill was headed to the hospital with her husband early Sunday when the car they were riding in was struck in a hit and run, killing them both, but their baby boy survived and was born prematurely, authorities and a relative said.

The driver of a BMW slammed into the livery car carrying Nachman and Raizy Glauber, both 21, at an intersection in the Williamsburg neighbourhood of Brooklyn, said Isaac Abraham, a neighbour of Raizy Glauber's parents who lives two blocks from the scene of the crash.

The engine of the livery car ended up in the backseat, where the pregnant woman was sitting before she was ejected, Abraham said. Her body landed under a parked tractor-trailer, said witnesses who came to the scene after the crash. Nachman Glauber was pinned in the car, and emergency workers had to cut off the roof to get him out, witnesses said.

Baby delivered by C-section, weighs 4 pounds

Both of the Glaubers were pronounced dead at hospitals, where doctors performed a cesarean section on the mother to deliver the baby. Both parents died of blunt-force trauma, the medical examiner said.

Their son was in serious condition, Abraham said. Neighbors and friends said the boy weighed only about 4 pounds. The hospital did not return calls about the infant.

Funeral services were held Sunday at a Brooklyn, New York synagogue for expectant parents Nachman and Raizy Glauber, both 21. They were killed when the car that was taking them to a hospital was hit. Their baby boy survived. (Verena Dobnik/Associated Press)

The Glaubers' livery cab driver was treated for minor injuries at the hospital and was later released. Both the driver of the BMW and a passenger fled and were being sought, police said.

On Saturday, Raizy Glauber "was not feeling well, so they decided to go" to the hospital, said Sara Glauber, Nachman Glauber's cousin. Abraham said the Glaubers called a car service because they didn't own a car, which is common for New Yorkers.

The Glaubers were married about a year ago and had begun a life together in Williamsburg, where Raizy Glauber grew up in a prominent Orthodox Jewish rabbinical family, Sara Glauber said.

Raised north of New York City in Monsey, N.Y., and part of a family that founded a line of clothing for Orthodox Jews, Nachman Glauber was studying at a rabbinical college nearby, said his cousin.

Brooklyn is home to the largest community of ultra-Orthodox Jews outside Israel, with more than 250,000. The community has strict rules governing clothing, social customs and interaction with the outside world. Men wear dark clothing that includes a long coat and a fedora-type hat and often have long beards and ear locks.

'They really were one soul'

Jewish law calls for burial of the dead as soon as possible. Hours after their deaths, the Glaubers were mourned by at least 1,000 people at a funeral outside the Congregation Yetev Lev D'Satmar synagogue. Men in black hats gathered around the coffins in the middle of the street, while women in bright headscarves stood on the sidewalk, in accordance with the Orthodox Jewish tradition of separating the sexes at religious services.

The sound of wailing filled the air as two coffins covered in black velvet with a silver trim were carried from a vehicle. A succession of men and women delivered eulogies in Yiddish, sobbing as they spoke into a microphone about the young couple. "I will never forget you, my daughter!" said Yitzchok Silberstein, Raizy Glauber's father.

Afterward, the cars carrying the bodies left and headed to Monsey, where another service was planned in Nachman Glauber's hometown.

"You don't meet anyone better than him," said his cousin. "He was always doing favors for everyone."

She said Nachman's mother herself just delivered a baby two weeks ago.

"I've never seen a mother-son relationship like this," Sara Glauber said. "He called her every day to make sure everything was OK. He was the sweetest, most charming human being, always with a smile on his face."

She added that, of him and his bride, "if one had to go, the other had to go too because they really were one soul."