Lt. Robert McCullough of the Baltimore County police said no charges have been filed in the case, but police did take evidence from Reed's residence.
McCullough said police entered Reed's home around 10:30 p.m. Tuesday to "investigate potential narcotics activities." McCullough said the evidence that was confiscated is being analyzed and Reed "currently is not being charged with anything."
"We're aware of the situation, and we have talked about it with David," said Kevin Byrne, the Ravens' senior vice president of public and community relations. "He'll have his due process and his opportunity to talk about the circumstances."
Should Reed be charged and convicted, he would be subject to the NFL's personal-conduct policy.
Reed, a fifth-round draft pick out of Utah, has made an impact on the Ravens as a kickoff returner. Reed has returned 14 kicks for a 26.1-yard average, including an 84-yarder in a Nov. 21 game against the Carolina Panthers.
The Associated Press contributed to this report.