After tracking an alleged drug dealer from Braintree for months, police arrested the 20-year-old man last Friday afternoon when they saw him allegedly sell marijuana to three people at his home on Cedar Street.

Matthew J. Mahoney was arrested after a subsequent search of his property turned up marijuana, cocaine and evidence of drug packaging, Chief Russell Jenkins said in a statement.

Mahoney was charged with possession of cocaine with intent to distribute, possession of marijuana with intent to distribute, distribution of marijuana and conspiracy to violate the Controlled Substances Act.

Ongoing surveillance of Mahoney came to fruition on Nov. 2 when detectives saw three people pull into his Cedar Street driveway, Mahoney approach them and then found marijuana in the car, Jenkins said.

The three men were not identified because they were not charged with a crime.

After identifying where the marijuana came from, Jenkins said, officers executed a search warrant at Mahoney's home, where they found the drugs and packaging material.