AYER -- A raid on a home here early Thursday morning led to the arrest of a man who police said was known to have firearms and could be dangerous.
The home at 93 Snake Hill Road had also been investigated for alleged drug-dealing, police said. Undercover officers had made controlled drug purchases before the raid.
The raid followed what police described as a lengthy investigation that included law-enforcement personnel from five communities.
Police arrested Robert Dumas, 57, on firearms, fireworks and numerous drug possession and distribution charges.
"A drug dealer is off the streets, and our communities are safer for it," Ayer Police Chief William Murray said.
Another man in the home at the time of the raid, Zechariah Guay, 23, of Shirley, was arrested on an unspecified outstanding warrant.
Investigators decided to use the Central Massachusetts Law Enforcement Council, or CEMLEC, SWAT team after determining Dumas could be dangerous to police. No one was injured in the raid, police said.
The raid turned up seven firearms, a "significant amount" of cash, marijuana and Percocet, a painkiller, police said.
Dumas was charged with possession of a firearm during commission of a felony, possession of an illegal stun gun, and improper storage of a firearm. Drug charges included two counts of possession of a Class B substance, two counts of Class B drug possession with intent to distribute, possession of Class D drugs with intent to distribute, and distribution of Class D drugs.
Police officials with those departments involved in the raid said they were proud of the work done by investigators and officers. Detectives from the Ayer, Acton, Groton, Boxboro and Littleton police departments were involved.
"This would not have been possible without the amazing level of cooperation that has been built up among municipal police departments in Massachusetts," Boxboro Chief Warren Ryder said. "This show of teamwork has given police an unprecedented ability to damage the drug trade and other illegal acts in our communities."
"This was a long-term case that required hours of investigation, hands-on drug buys, and careful execution," Groton Police Chief Donald Palma Jr. said. "I am proud of each of the officers involved, who helped bring a drug dealer to justice."
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