WEST PARIS – A West Paris contractor was arrested Wednesday at his home where police found heroin ready for distribution, marijuana, 21 firearms and thousands of dollars in cash.

Michael Holden, 44, of 2 Bog Brook Loop, was taken into custody after state and local law enforcement officers arrived at his home about 1 a.m. while he and his wife were asleep, police said.

The self-employed excavation contractor was booked at the Oxford County Jail in Paris at 3:27 a.m. and charged with aggravated trafficking of heroin, a Class A felony, according to reports. Jail officials said he was released on $1,000 bail about 10:45 a.m.

The arrest was the result of a three-month investigation by the Maine Drug Enforcement Agency. The probe was led by an area police officer who had gotten reports that Holden was obtaining heroin from out-of-state and selling it from his West Paris home, according to a statement from the Maine Department of Public Safety.

Agency officials obtained a search warrant after gathering evidence of dealing, MDEA supervisor Tony Milligan said. He would not reveal details of the investigation but did say undercover officers were used.

Officers seized more than two grams of heroin “packed and ready for distribution,” recently harvested marijuana, 21 firearms, some of them loaded, and more than $3,200 in cash, according to the department statement.

Also recovered were scales, hypodermic needles and “an assortment of drug paraphernalia,” the statement said.

If convicted on the trafficking charge, Holden could face up to 40 years in prison.

Holden does not have a history of charges related to heroin, Milligan said.

The street value of heroin is about $300 a gram, Milligan said, and it is sold in doses of about a tenth of a gram.

The amount of heroin recovered at Holden’s home wasn’t that substantial, Milligan said, however the charges are serious given that it was packaged in doses.

The Oxford County Sheriff’s Office and Maine State Police helped with the investigation.

Holden has not been arraigned in court. A grand jury will hear his case Oct. 4, according to court officials.