Police say three violent robberies of women who had been by themselves on D.C. streets during the past week are likely related.

The first attack was reported around 10 p.m. May 15 at the intersection of C and 9th streets SE. A 67-year-old woman said a stranger wrapped his arm around her neck and told her to be quiet.

She offered her purse, and the suspect took it -- but not before stabbing her in the neck, leaving a six-inch wound.

The second was reported Wednesday evening around 9:15 p.m. in the 400 block of M Street NE close to Gallaudet University. A woman in her 20s was walking alone when a man grabbed her from behind and robbed her at knifepoint. She was not injured.

Approximately 30 minutes later, a similar attack was reported near the intersection of Independence Avenue and 8th Street SE. A woman in her 20s walking alone reported being grabbed from behind and robbed at knifepoint. She was stabbed in the neck and is expected to be OK, though the extent of her injuries is unknown.

This week, police released surveillance video from a Citgo gas station. They say a man wanted in connection with the May 15 assault is seen possibly offering to pump gas for other customers.

Though police wouldn't say the man in the video is wanted in all three assaults, Captain William Fitzgerald said the victims' descriptions of their attackers are similar.

The attacks happened several blocks from the area where a man in his 60s was robbed and assaulted earlier this month. He died from his injuries several days later, and two men have been charged in his death.

If you have any information for police, call 202-727-9099.