Fourth person arrested in 2012 Richmond Hill explosion

Two people died in the November 2012 explosion in Richmond Hill.

A fourth person has been arrested in the November 2012 Richmond Hill house explosion.

Gary Thompson, 44, faces two charges of murder in connection with the explosion, which killed Dion and Jennifer Longworth and destroyed dozens of homes on the Indianapolis south side.

Thompson was arrested Wednesday.

His arrest comes eight days after Monserrate Shirley struck a plea deal and agreed to work with prosecutors.

Court records show Thompson is charged with two counts of murder. Although the victims aren't named, the murders occurred the same day as the Richmond Hill explosion, which killed the Longworths.

Gary Thompson's has an arrest history stemming from repeated driving violations. Arrest records show Thompson had a habit of getting behind the wheel unlawfully.

In December 2008, Thompson was taken into custody as a habitual traffic offender. He had been caught driving while suspended. It was his second driving arrest in less than a two-week period.

In late November of that year, police caught him speeding and discovered Thompson had been ordered off the road for ten years, until 2018. The suspension was the result of a 2007 conviction for operating while intoxicated.

Based on police reports portable breath tests in that 2007 case registered .21, nearly three times the legal limit for driving drunk.

Like his co-defendants Mark and Bob Leonard, there was nothing in Thompson's criminal history suggesting involvement with explosives. Until now, his history reveals low-level crimes that kept him in and out of jail.

Prosecutors have not said if they will seek murder without parole for Thompson. More information is expected Thursday.

Monserrate Shirley guilty plea

In her plea agreement, Shirley described how she conspired with her then-boyfriend Mark Leonard and his half-brother Bob Leonard to blow up her home to collect insurance money.

According to Shirley, they had the assistance of an "unnamed" individual. That person helped in two failed attempts. On the third try, according to Shirley's statement, Bob Leonard and the uncharged individual "completed the overt act of tampering with the natural gas line" and created the ignition source so that when the home filled with natural gas it would cause an explosion or fire.

In addition to killing two neighbors, the fiery explosion destroyed or damaged more than 100 homes.

The Marion County prosecutor postponed an afternoon news conference until Thursday.

One of the questions to be answered is if Thompson the "uncharged" individual referred to in court documents, and if there are any further arrests expected or additional charges against Thompson.

As part of the plea agreement, Shirley agreed to testify against the other two defendants, Mark and Bob Leonard, and anyone else who is charged in the November 2012 case. All other counts against her will be dismissed. Shirley's prison sentence will be left for the judge to decide after trials for the Leonards have taken place.

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