SPRINGFIELD, Mass. (AP) — Springfield police have arrested three people and seized nearly 17,000 bags of heroin.

The arrests Thursday morning were made after a lengthy investigation into what police call major distributors of heroin throughout western Massachusetts.

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The suspects, Jeremy Crespo, of Holyoke, and Moises Silva and Jereiska Fontanez, both of Springfield, are being held without bail and face arraignment Friday on drug and gun charges.

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The two men were tailed by police through several cities where they allegedly made drops to street-level dealers. They were arrested in a gas station parking lot.

Investigators then executed a search warrant on an apartment where they arrested a woman and found the heroin, as well as cocaine and marijuana, more than $11,000 in cash, a loaded gun and drug weighing and packaging paraphernalia.

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