The six-plus kilos of raw heroin, once milled or processed and packaged for resale, would have a “conservative” street value of $1,350,000, Hampden District Attorney Anthony Gulluni said.

Investigators seized the raw heroin from 73 Cherrelynn St. which served as a large-scale heroin processing factory or mill with a set-up that could accommodate some 6 to 8 workers as they milled the heroin, mixed it with cutting agents and then packaged and stamped it for distribution onto the street.

Gulluni praised those who participated in the investigation and raids, which also yielded 4,500 bags of ready-for-sale heroin, six firearms and four motor vehicles.

“This was a high-level and sophisticated operation that was supplying this area with heroin,” he said. “The streets and neighborhoods here in Hampden County are appreciably safer today with these individuals in custody.”

The raids, conducted simultaneously at 6:30 a.m., followed several months of extensive intelligence gathering, investigators said.

Investigators uncovered a smaller milling operation at 57-59 Sterling St., the home of one of the primary targets, Josue Pujols. That property also served as housing for the heroin mill workers.

From that property they seized approximately 1.5 ounces of uncut heroin, four shotguns, two loaded handguns and multiple baggies, grinders and packaging materials consistent with a small mill.

Massachusetts State Police Colonel Richard McKeon, U.S. Drug Enforcement Administration Special Agent in Charge Michael Ferguson and Springfield Commissioner John Barbieri also participated in the press conference. It was held in a conference room at 1441 Main St.

McKeon said the success of the investigation was the result of close coordination and cooperation among the law enforcement partners, a model that is vital to large-scale drug operations.

“The defendants and locations we targeted in this network were critical components of a significant distribution network in this area,” he said.

Ferguson added, “Those suffering from the disease of opioid addiction need access to treatment and recovery. But those responsible for distributing lethal drugs like heroin and fentanyl to the citizens of Massachusetts need to be held accountable for their actions.”

Ferguson said such heroin mills started appearing in Massachusetts about a year-and-half ago. “There is more profit if they do it this way,” he said.

Some of the heroin seized from this particular organization before this particular bust was found to be laced with fentanyl, Ferguson said. The heroin seized Monday has yet be tested.

Barbieri gestured at the seized evidence on display, including the six firearms, as he spoke to the violence that is intrinsic to the drug trade. “I ask everybody here to look at these two tables,” he said. “They are full of violence and pain.”

Arrested at 57-59 Sterling St., which is in the Liberty Heights neighborhood, were Astrun Pujols, Miguel Sanchez, and Josue Pujols, all of Springfield.

All three were charged with possession of a firearm without a license (a total of three counts for Josue Pujols). That latter suspect was also charged with trafficking heroin (18-36 grams).

Arrested at 73 Cherrelyn St., which is also located in the Liberty Heights neighborhood, were: Springfield residents Elvis Pujols and Harlem Ciprian; Queens, N.Y. residents Yankey Ciprian, Edward Ciprian and Franky Mosquea and Bronx, N.Y. resident Richard Capran.

All six were charged with trafficking in heroin over 200 grams.

The final arrest was the target of the operation and the subject of an arrest warrant, Fausto Pujols of Springfield. He was arrested at an unrelated fifth location by the state police Violent Fugitive Apprehension Section.

Fausto Pujols was charged with trafficking heroin (over 200 grams) conspiracy to violate drug laws and heroin distribution. He is believed to have orchestrated the milling operation at 73 Cherrelyn St.

The suspects are slated to be arraigned in District Court. Investigators said the investigation is ongoing.

The raids were conducted by DEA agents, state troopers attached to Gulluni’s office, troopers from the state police narcotics unit, the FBI Gang Task Force. Springfield narcotics detectives and agents from both the IRS and ATF.

Gulluni made a point to particularly praise the work of state police Trooper Michael Scott and Assistant District Attorney Kerry Beattie during the investigation.