TULSA, Oklahoma - News On 6 has uncovered new information about a recent drug bust at an Owasso home. We've learned there's a connection between that home and the Irish mob gang.

In an exclusive story, we can tell you how Broken Arrow police and ATF agents have spent the past year investigating that gang's drug trafficking in Green Country.

Investigators say the Irish mob gang started in west Tulsa off 33rd West Avenue. They wear the color green, shamrocks and Celtics jerseys, especially Larry Bird's old No. 33.

An affidavit says when police made the drug bust in Owasso, they found "33" and a shamrock spray painted on the garage walls.

Police said that by looking at the outside of it, you never could tell what was going on in the inside of the house that sits in a quiet Owasso neighborhood.

10/30/2015 Related Story: Welfare Check Results In Owasso Drug Bust, 2 Arrests

Broken Arrow investigators say the Irish mob is involved in drug trafficking, receiving stolen items, robberies and home invasions.

Unlike other gang members, a lot of the Irish mob members don't just sell drugs, they also do drugs, TPD said.

"They get strung out on meth and heroin and are constantly doing burglaries, stolen property, things like that,” TPD Organized Gang Unit Sgt. Sean Larkin said.

Tulsa's gang unit arrested Derrek Merryfield on Wednesday for drugs. He has IMG, for “Irish Mob Gang” tattooed on the side of his neck.

Police say the Irish mob is a big prison gang, but members don’t get along with other white gangs.

Members of the IMG got into a huge fight recently with members of the United Aryan Brotherhood at the prison in Cushing, and four people ended up dead and others injured.

But police said innocent citizens are not likely to fall victim to IMG violence.

"Often they are robbing and stealing from each other,” Larkin said. “Shootings, the general public, the chances are so small of it happening to somebody."

In Owasso, Michelle Krafft-Griggs went to jail for aggravated trafficking and having a gun during a felony.

They say they found more than 50 pounds of marijuana and some meth.

An affidavit says she had pictures of prisoners with Irish mob tattoos and letters from prisoners, money transfer receipts and payment slips for a storage unit in Broken Arrow.

Broken Arrow police got a warrant for the storage unit, but when they got there days later, they found nothing.

One website says the Irish mob has been reported in 13 locations in the U.S. Five of them were in Oklahoma -- Tulsa, Catoosa, Norman, Oklahoma City and the state prison system.