Erie, Pa. ? A small plane attempting to land Saturday night crashed about a half-mile short of the runway at Erie International Airport, killing three people and injuring a fourth, airport police said.

The pilot had apparently stopped to get gas in Jamestown, N.Y., but was unable to do so, airport police chief David Bagnoni said.

“My assumption is, they ran out of gas,” Bagnoni said.

Two men and a woman were dead at the scene, he said. Another woman was airlifted to a hospital, where a spokesman said her condition was being evaluated.

The victims were from Delaware, and may have been on their way back, Bagnoni said. Their names were not immediately released.

The Federal Aviation Administration was investigating the crash, authorities said.