NEW YORK (AP) - A baby delivered after his parents were killed in a New York City hit-and-run accident died early Monday, a community spokesman said.

Isaac Abraham, who serves as a spokesman for the city's conservative Orthodox Jewish community, said the child died early on Monday.

The infant had been in serious condition after doctors performed a cesarean section on his mother to deliver him.

Police were searching for the driver of a BMW and a passenger who fled on foot after slamming into a cab, killing the young pregnant woman and her husband on the way to a hospital.

"We in the community are demanding that the prosecutor charge the driver of BMW that caused the death of this couple and infant ... with triple homicide," Mr Abraham said in a statement. "This coward left the scene of the accident not even bothering to check on the people of the other car."

Police spokesman Paul Browne declined to say on Monday whether investigators have a specific suspect in mind.

Police said the registered owner of the BMW, who was not in the car, was charged with insurance fraud. Police said Takia Walker, 29, was arrested Sunday.

New York City's ultra-Orthodox Jewish community, the largest outside of Israel, wept at the couple's funeral Sunday, just hours after the couple's deaths. Jewish law calls for burial of the dead as soon as possible.

Nachman and Raizy Glauber, both 21, had been looking forward to welcoming their first child.

In the crash, the cab's engine ended up in the backseat, where Raizy Glauber, who was seven months pregnant, was sitting before she was ejected, said Mr Abraham, a neighbor of her parents. Her body landed under a parked truck, witnesses said. Nachman Glauber was pinned in the car, and emergency workers had to cut off the roof to get him out, witnesses said.

Both were pronounced dead at hospitals, and the medical examiner said blunt-force trauma was the cause.

Neighbors and friends said the baby had weighed only about 4 pounds (1.8 kilograms).

On Saturday, Raizy Glauber "was not feeling well, so they decided to go" to the hospital, said Sara Glauber, Nachman Glauber's cousin.

Mr Abraham said the Glaubers called a car service because they didn't own a car, which is common for New Yorkers.

The cab driver was treated for minor injuries and released.