JACKSON — Three people have pleaded guilty to conspiring to distribute Mexican methamphetamine as part of what authorities called the biggest meth ring ever brought down in Mississippi.

Authorities arrested dozens of people in a massive sweep last June as part of what they said was a multimillion dollar distribution network with ties to Alabama, Florida and Texas. Investigators said the group distributed more than 50 pounds of Mexican meth a month.

Richard Scott Morea, David Gene Johnston and Diana L. Pearson are the first of 19 people charged in a federal indictment to plead guilty in the case. They entered the pleas Wednesday before U.S. District Judge Keith Starrett in Hattiesburg, court records said.

Sentencing was set for April 20.

Dozens of others have been charged in state court in the investigation.

Nearly 100 guns, several silencers and at least $1.5 million worth of meth were seized along with stolen cars, motorcycles and all-terrain vehicles after an 18-month investigation, Mississippi Bureau of Narcotics Director Marshall Fisher has said.

Court records did not indicate if Morea, Johnston or Pearson had agreed to cooperate and help authorities with the case.

Morea and Pearson pleaded guilty to conspiring to distribute more than 500 grams of the drug, a charge that carries a possible sentence ranging from ten years to life.

K.C. Hightower, the Hattiesburg attorney who represents the 35-year-old Pearson, said he had no comment on the case or whether his client is cooperating with prosecutors.

Johnston, 35, pleaded guilty to conspiring to distribute more than 50 grams of meth and faces a sentence of five to 40 years.

"He just accepted responsibility for his role in the conspiracy" and is ready to move on with his life, said Johnston's attorney, Tracy Klein of Hattiesburg.

Klein said there was no "plea bargaining" involved.

Morea's attorney, Andy Sumrall of Jackson, had no comment.

Authorities claim that the ring was highly organized and violent.

Some suspects were caught on tape discussing a plan to break into a narcotics office in Mississippi to steal back their confiscated drugs, authorities have said. Authorities said they also wanted the identities of narcotics agents and judges involved in the case.

John Colette, who represents the accused ringleader of the group, has said nobody was threatened in the intercepted phone calls and people just wanted to know what authorities they were dealing with.