An 85-year-old Northwest woman was fatally injured Thursday afternoon by what police called a speeding getaway car that knocked her 155 feet and left her lying in the street. The woman, who suffered two broken legs, and broken arm and severe head and internal injuries, died 13 hours later.

Hele Helbert, a nurse and housekeeper for 30 years, was walking across Albermarle Street NW on her way home from getting a flu shot when she was hit by a car as it sped through a red light at Connecticut Avenue at a speed of 45 to 50 miles an hour, police investigators said.

Police arrested two suspects in the aborted bank robbery at the Tenley Circle branch of American Security Bank a short time after the hit-and-run, but police said that a third suspect, believed to be the driver of the car, escaped.

"It's a great loss; she was like one of the family," said Rosa Kraft, in whose residence at 2844 Albermarle Helbert lived and worked. "She was very vital mentally and physically, always running up and down the stairs."

The series of events started about 1:30 p.m. Thursday when a man entered the branch bank at 4445 Wisconsin Ave. NW, walked up to teller Martin Bowman and told him, "Lay the stack of hundreds on the counter."

When Bowman refused, the man screamed, "Gimme the money, gimme the money!" and threw a floor ash can at the Plexiglas teller's window that protected Bowman. He than ran.

Police said the man in the bank fled with two other men in a dark blue, 1966 Ford Futura. Witnesses saw a car hit Helbert and sideswipe at least one ofter car before continuing east on Albermarle.

Police said they broadcast a lookout for the car and that it was stopped at the intersection of Columbia Road and Adams Mill Road.

Two persons arrested were identified as Joseph Thurston Lockett, 33, of 6517 Eighth St. NW, and Preston Kirby Procter Jr., 43, of 1916 Village Green Dr., Hyattsville.

Lockett and Proctor were charged with attempted bank robbery, police said, but no charges have been filed in Helbert's death, pending an investigation.