TEXARKANA (AP) — Federal prosecutors have charged 66 people with selling crack cocaine and methamphetamines near schools and public housing in western Arkansas, authorities announced Tuesday.

The indictment lists 190 counts ranging from drug possession with intent to distribute to the illegal possession of a 12-gauge shotgun, handguns and other weapons. Dozens of people were caught selling drugs between June 2010 and this August, the indictment alleges.

A total of 76 people face federal and state charges due to "Operation State Line Sweep," which primarily focused on the city of Texarkana, which is split between Arkansas and Texas. So far, 41 people have been arrested.

Several agencies and about 100 law enforcement officers were involved in the yearlong investigation, U.S. Attorney Conner Eldridge said at a press conference Tuesday. Eldridge said the dozens of people indicted due to the investigation were involved in a conspiracy to distribute crack cocaine.

"This is a significant operation that we believe makes the streets of Texarkana safer and makes great headway in the drug trafficking issues that plague some of the streets and have plagued this area," Eldridge said.

More than a dozen defendants are accused of selling drugs at or near Pinehurst Village, a public housing complex in Texarkana. Others are accused of selling near five public schools and a playground in the city.

Eldridge’s office said the investigation included "a number of controlled buys" from defendants.

Dave Shepard, assistant special agent in charge for the FBI’s Little Rock office, declined to discuss details of the investigation because cases against defendants were still pending.

The investigation marks the third major drug bust in Arkansas in as many weeks. On Oct. 4, Eldridge’s office announced 54 drug arrests in four southern Arkansas counties.

Federal prosecutors in eastern Arkansas last week announced the indictments of 70 people — including five law enforcement officers — as part of a four-year investigation into drug trafficking and corruption in eastern Arkansas.

Eldridge’s office says there aren’t any known connections between last week’s investigation, known as "Operation Delta Blues," and the one announced Tuesday. No law enforcement officers were arrested in this investigation.

Michael Johnson, a visiting professor at the University of Arkansas at Little Rock’s law school, said that the three investigations appeared to have significant differences. Though drugs move through Arkansas on Interstates 30 and 40, those shipments don’t necessarily influence drug activity in local cities, Johnson said.

"Drug trafficking and drug usage is very prevalent," Johnson said. "I think Arkansas is no different from any others in that regard."

Eldridge, in an interview Tuesday, said there was "no question that drug trafficking is a big issue" in his district, which also includes Hot Springs, Fort Smith and Fayetteville.

"We also understand that activity and that criminal activity is something that law enforcement and criminal prosecutors have to keep constant vigilance on," he said.

It was not immediately clear if defendants in the case had attorneys yet.