FOUR people have been arrested in connection with drugs found at the home of film star Philip Seymour Hoffman following his death of an apparent heroin overdose.

The arrests came during a raid on a building in the Chinatown district of Manhattan after police traced the heroin believed to have killed the Oscar-winning actor there, the newspaper reported.

A New York City Police Department spokesman said officers found narcotics at the building in Chinatown and four people were arrested..

Meanwhile, police have said heroin found in Hoffman's apartment following his death was not cut or mixed with fentanyl, a synthetic narcotic believed by health authorities to be responsible for scores of overdose deaths in recent months.

The 46-year-old actor was found unresponsive on the bathroom floor of his Manhattan apartment on Sunday by police responding to an emergency 911 call.

Police found Hoffman with a syringe in his arm and recovered plastic bags containing a substance believed to be heroin.

Hoffman, who is survived by his partner, Mimi O'Donnell, and their three children, had detailed his struggles with substance abuse in the past.

The actor, who earned an Academy Award for his portrayal of Truman Capote in the 2006 drama Capote and was considered one of the most gifted film stars of his generation.