D.C. police are investigating a sexual assault and an attempted sexual assault that occurred Saturday in Northeast and Southeast Washington, both involving men armed with knives, according to authorities. Police said they do not believe the two attacks are related.

The first occurred about 5:15 a.m. in the 4200 block of 7th Street SE. Police said a man armed with a silver knife broke into a woman’s apartment, sexually assaulted her and then ran out.

Police released no other details of the attack, and had only a scant description of a man between 5 feet 3 and 5 feet 7 inches tall wearing black clothing, a black mask and gloves.

On Saturday night, police said a man armed with a pocket knife attacked a woman near the Noma-Gallaudet Metro station on New York Avenue.

Police said the woman was walking in the 300 block of Florida Avenue NE about 7:30 p.m. when the man forced her into an alley. Police said the man tried to sexually assault her but she yelled for help and the man ran away.

Police said the man is described as black, in his late 40s, standing 5 feet 8 inches to 5 feet 9 inches tall and weighing about 150 pounds. He has a brown complexion, brown eyes, missing teeth, a mustache and had cuts on his arms. Police said he was last seen wearing a grey short-sleeve shirt, black jacket, black shoes and dark jeans with either a shoe-string or flex-cuff.

Anyone with information is urged to call D.C. police at 202-727-9099 or text the department’s tip line at 50411. Police are offering a $1,000 reward for information leading to an arrest and conviction of a suspect in each of these cases.

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