Police in the District and Montgomery County are investigating two fatal pedestrian collisions, one of which was a hit-and-run that occurred over the weekend.

The first incident took place shortly after midnight Saturday when a pedestrian was struck and killed while crossing Suitland Parkway, U.S. Park Police reported.

The woman, a 27-year-old resident of the District, was crossing the westbound side of the parkway at Naylor Road when she was hit. The car that struck her left the scene.

Park Police ask anyone who witnessed the crash or who has information to call 202-610-8737.

The second collision occurred at about 7:25 a.m. in the intersection of southbound Georgia Avenue and Windham Lane in Wheaton.

Montgomery County Police reported that 52-year-old Victor Noel Williams was hit as he stepped off the curb. Williams, of the 2900 block of Peregoy Drive in Kensington, was transported to Holy Cross Hospital, where he died from his injuries.

The driver, Armida Herrara of Silver Spring, remained at the scene after the collision. She was not injured. The crash remains under investigation.