The state attorney general's office made history Wednesday with what officials described as the largest drug takedown in the office's history, in Methuen and Lawrence.

"As a result of this operation we dismantled a major drug trafficking operation in the Northeast region of this country," said Attorney General Maura Healey. "This operation of our Fentanyl Strike Force is a culmination of a two-year investigation that involved extensive surveillance of a sophisticated narcotics operation that spanned our region and was overseen by higher-ups as far away as New Jersey."

Healey was joined by state, federal, and local police at a press conference to announce the takedown, which resulted in the arrests on Wednesday of 12 individuals in Lawrence and Methuen and the seizure of four guns, almost $100,000 in cash, and more than 24 kilos of heroin, fentanyl and cocaine. Eight of those arrested lived in Lawrence and four lived in Methuen.

"To put this in context, 24 kilos that we seized represent, and you can see them here on this table today, that represents what you're looking at, millions of dollars worth of drugs," Healey said. "As importantly, if not more importantly, it represents hundreds of thousands of lethal doses of drugs that we have kept from affecting communities in our state."

Police executed search warrants for 14 locations in Methuen and Lawrence on Wednesday, in an operation that involved over 100 members of law enforcement. The individuals arrested are from several levels in the distribution chain, officials said.

Law enforcement officials emphasized the importance of getting the seized drugs out of local communities.

"This underground economy has a direct and detrimental impact on countless lives and knows no boundaries, geographic, economic, or otherwise," said Methuen Police Captain James Jajuga Jr.

Associate Special Agent in Charge for the U.S. Drug Enforcement Administration New England John DeLena said the DEA will continue to work to keep dangerous drugs off the streets.

"With the arrests highlighted today and the seizure of fentanyl and drug proceeds and guns we know this will have a very positive impact on all of our communities," DeLena said. "We have witnessed the destruction that the opioid epidemic has brought to each and every one of our neighborhoods. That is why we are here today."

Healey also spoke about the success of the Fentanyl Strike Force, which has seized 227 kilos of drugs, 14,000 opioid pills, and arrested nearly 300 people since its creation in 2016.

"We know this job isn't over, but this critical work, critical collaboration is paying off," she said. "Together with our law enforcement partners we are arresting and prosecuting those engaged in criminal drug operations here and across the Northeast, we're dismantling major drug networks and we're taking millions of lethal doses of heroin and fentanyl off the street. Every drug we take off the street is potentially a life saved."

Healey and law enforcement officials emphasized the importance of interagency cooperation, and how the success of the operation was due, in part, to the cooperation of local, state and federal police.

"This crisis is too big for any one agency to tackle on its own," Healey said.

Michael Kroll, assistant special agent in charge for Homeland Security Investigations in Boston, spoke about the need to tackle these issues across government lines.

"We all know too well that tackling this complex threat involves a united comprehensive strategy and an aggressive approach by multiple entities across all levels of government," he said.

Those arrested will now face charges of conspiracy to violate the Controlled Substance Act for Fentanyl and Cocaine trafficking, and face up to 20 years in prison.

All agencies said they would continue to work to fight the opioid epidemic.

"It is our collective hope that by reducing the availability of these dangerous and deadly drugs we are able to spare families and friends the heartache of addiction and the loss of a loved one," said State Police Colonel Kerry Gilpin.