NEWARK, N.J. (AP) -- Law enforcement officials say more than 30 people have been arrested for roles in a ring that allegedly sold about $1 million in drugs over the past three months.

David Matthau, Townsquare Media NJ

Acting Essex County Prosecutor Carolyn Murray says the arrests announced Monday stem from an ongoing investigation dubbed "Operation Joint Effort." It involved 26 law enforcement agencies on the federal, state, and local levels.

Murray says the investigation found that various drugs were being sold within the Route 21 Corridor.

"We have interrupted and intercepted a middle-level distribution ring that is not just supplying heroin to the city of Newark, but is supplying heroin out into the suburban towns," Murray said.

Authorities seized 518 bricks of heroin and made 31 arrests during early morning raids Sunday in several towns in northern Jersey. An undetermined smaller amount of cocaine and marijuana was also seized, along with nine high-end vehicles more than $71,000 in cash.

Acting New Jersey Attorney General John Hoffman said the state must continue to combine strong law enforcement with a holistic approach, and options including treatment and drug courts.

"We’re pretty confident that kind of approach is going to be pretty successful and we’re going to win out, but it’s going to take some time, energy, effort and commitment," Hoffman said. "Criminals do not respect jurisdictional boundaries, and therefore we need police departments throughout the region to understand the criminal environment more broadly than just what occurs in just their own city limits."

David Matthau contributed to this story.

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