St. Louis County Police Chief Tom Fitch said DNA shows the same man committed both assaults, the St. Louis Post-Dispatch reported. One woman was raped in her apartment in the northwestern part of the county in February 2011, and the other about 5 miles away last month by a man who grabbed her on the street late at night.
Both victims were Asian-American.
The man may have assaulted other women in the area, Fitch said, telling the newspaper rape is the most underreported crime.
"We're trying to determine if this is a transient person, who is moving from city to city for a job, and see if there are links in those other cases," he said. "That makes it even more difficult to catch someone when they're mobile like that. But it could turn out that he was born and raised here as well."
So far, investigators have found no links to sexual assault cases in other jurisdictions.