TRENTON, N.J. (CBSNewYork) – Police in New Jersey have taken down a major drug ring operating across the state.

Authorities say 28 people were arrested in the sting and investigators seized nearly 40,000 doses of heroin and fentanyl from the suspects.

Police also found 22 guns, including five assault rifles, during the busts in Trenton and Paterson.

New Jersey’s attorney general said a long-term investigation helped take down the two opioid mills.

“When we bring enforcement actions, we do it the smart way, not by rounding up every person on every corner but by going after the most dangerous criminals and by targeting the sources of the guns and the drugs that plague each of our cities and our streets in our state,” Gubir Grewal said.

Among those arrested were 10 members of the “4-K Boyz Bloods” gang, including their reputed leader, Kashard Whitaker.