D.C. police are investigating two cases of sexual assault in Northeast Washington.

About 11 p.m. Thursday, a man allegedly attacked a woman at gunpoint in the 1300 block of 45th Place NE, police said.

The suspect is described as a black man with medium complexion, 15 to 22 years old, weighing about 165 pounds. The man wore tan pants and a white polo shirt with green and blue stripes, police said.

Earlier this week, police said a woman was allegedly attacked about 11 p.m. Monday in the 400 block of Taylor Street NE.

Investigators described the suspect as a black man with medium complexion, 22 to 26 years old, weighing about 180 pounds. He was cleanshaven, had short hair and wore a white T-shirt, police said.

Investigators so far have found no evidence to show that the attacks are related, a police spokesman said.

Anyone with information on either case can call police at 202-727-9099 or send a text message to 50411.