Minneapolis police expect to release a composite sketch next week of a suspect who may be responsible for two sexual assaults on women last Saturday near the University of Minnesota and in Fridley.

They're also trying to determine whether a third incident may be by the same person. In the most recent one, a woman said two men tried to abduct her as she walked alone just after midnight early Wednesday near TCF Bank Stadium.

Police spokeswoman Cyndi Barrington said investigators are following numerous leads and are comparing the attacks. Police already have said they believe the first two attacks, which occurred just hours apart, to be the same man, who posed as a police officer.

In the second university incident, a car with two men inside pulled up to a woman and asked if she needed help. The passenger got out and tried to get the woman into the car, a dark blue sedan. She used pepper spray on him, then he threw her to the ground, used the spray on her and left when she screamed.

Barrington said that investigators are comparing the latest report to the earlier incidents, but that it's too early to say whether they are connected.

In the first two incidents, the attacker drove a small, dark-colored SUV with what appeared to be a computer on the dashboard. Minneapolis police described the suspect from the first university attack as a black man, 23 to 27 years old, with short hair or a shaved head and a neatly trimmed chin-strap-style beard.

In the Fridley case, the suspect was described as a black male about 6 feet tall, 190 pounds, with a thin beard, wearing a dark cap, sweatshirt, sunglasses and jeans.

In Wednesday's incident, the car's passenger was described as a black man with a medium complexion, 20 to 25 years old, about 6-foot-2 to 6-foot-4, with a medium build. He wore a black knit stocking cap and a black puffy jacket. A description of the driver wasn't available.

Anyone with information is asked to call the Minneapolis police tip line at 612-692-8477 and refer to case number MP-13-394848.

Police also have warned students to be aware of their surroundings.