Bobby Brown Jr. was found dead on November 18 at only 28 years old. The cause of death has been revealed and now a criminal investigation is reportedly underway.

According to NBC News, an autopsy report released by the Los Angeles County Coroner said Brown died due to combined effects of alcohol, cocaine and fentanyl.

The report also stated "no drugs or drug paraphernalia" were found at the scene. However, 

TMZ exclusively reports  the “drug-related death raised a lot of red flags with the police.”
The LAPD reportedly opened a criminal investigation “that's now in the hands of prosecutors.”

Sources told TMZ the LAPD “quickly caught on to the drugs after talking to people Bobby was around shortly before his body was found.”

The case is allegedly with L.A. County D.A.'s Office but no arrests have been made as of yet.

RELATED: Bobby Brown Pays Tribute To His Daughter Bobbi Kristina Brown On Fifth Anniversary Of Her Death

The 28-year-old was the half brother of Bobbi Kristina Brown, 22, who died five years ago after she was found unresponsive and not breathing in a bathtub at her Roswell, Georgia home. After being treated in a hospital and later put on life support for nearly six months, Bobbi Kristina died in July 2015. An autopsy showed her cause of death to be drug intoxication and immersion which led to pneumonia and brain damage.

Brown Jr. is one of Bobby’s seven children and is the son of Kim Ward, who Bobby Brown Sr. reportedly dated before he got engaged to singer Whitney Houston. The couple wed in 1992 until 2007. Houston died in 2012 after an accidental drowning in a bathtub, a coroner ruled heart disease and cocaine as contributing factors. 

According to Deadline.com, Bobby Brown Jr. was 13 when he appeared on the family’s 2005 Bravo reality show, Being Bobby Brown.