Indiana police found marijuana and other unidentified controlled substances on rocker Bret Michaels’ tour buses, The Fort Wayne News-Sentinel reported Friday.

Two tour buses, one of which carried the rock star, were pulled over in DeKalb County, northeast Indiana, before midnight local time Wednesday.

Police stopped the caravan because a trailer connected to one of the buses did not have a license plate light.

SLIDESHOW: Bret Michaels' Rock Star Career

Officers launched a drug search on the first bus after narcotics-detection dogs reportedly began acting strangely, The DeKalb Star reported.

Police then searched the second bus, where Michaels was a passenger, and also found illegal drugs. The veteran rocker was reportedly very cooperative in allowing the searches.

Police made no arrests but charges have been forwarded to the DeKalb County Prosecutor's Office. Both buses were allowed to continued.

Michaels, former frontman of rock band Poison and the 2010 winner of the “Celebrity Apprentice 3,” is currently on his “Roses & Thorns” tour in the U.S.

The 47-year-old recently overcame a brain aneurysm and a “warning stroke” earlier in 2010.