BOSTON (AP) — Authorities in Massachusetts have arrested 14 people and seized more than 24 kilograms (53 pounds) of fentanyl, heroin and cocaine in the bust of a major drug trafficking ring.

State Attorney General Maura Healey said Thursday it’s the biggest takedown of a major opioid trafficking operation in the history of her office.

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Authorities arrested 12 people Wednesday and seized $100,000 in cash and four guns during a series of raids in Lawrence and Methuen. Two people were arrested previously.

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The arrests were the result of a two-year federal, state and local investigation launched by special agents at the U.S. Drug Enforcement Agency office in Manchester, New Hampshire, who sought the source of drugs coming into that state.

Healey said the investigation used high-tech surveillance techniques as well as traditional law enforcement methods.

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