As the investigation into actor Philip Seymour Hoffman's death continues, police have arrested three people on drug charges.
The three -- Robert Vineberg, 57, Max Rosenblum, 22, and his girlfriend Juliana Luchkiw, also 22 -- were arrested during a raid on a building in Lower Manhattan. Police were tracing what they believed to be the source of the heroin suspected of playing a role in the Oscar-winning actor's death. A fourth person was also arrested in the raid, but charges against him were later dropped, The New York Times reports.
What will prosecutors need to prove to make their case?