Bobby Brown is being investigated for driving under the influence of an unknown substance.
On Monday afternoon around 12:20 p.m., the New Edition singer was pulled over on a Los Angeles road while chatting away on his cell phone.
Law enforcement officials tell TMZ that it's unclear as to what substance Brown, 43, had been using before he got behind the wheel of his vehicle.
On Thursday, the autopsy results for Brown's ex-wife, Whitney Houston, were released and ruled her main cause of death as an accidental drowning. However, there were also traces of cocaine found in her system, that may have caused her to go into cardiac arrest.
Brown and Houston, who was 48 when she died in her room at the Beverly Hilton Feb. 11, were married from 1992 to 2007 in a union that was often volatile. Houston said in 2009 that Brown "slapped her" and "spit in my face" during one argument. "He was my drug," she explained of their passionate dynamic.
Brown and the late "I Will Always Love You" singer share a daughter, Bobbi Kristina, 19.