A Lafayette grand jury on Wednesday indicted former Knight Oil Tools CEO Mark Knight, one of his employees and two former law enforcement officers in the framing of Knight’s brother on drug charges in a plot to push him out of the family business.

Mark Knight, former Knight Oil Tools employee Russell Manuel, former State Trooper Corey Jackson and former Lafayette Parish sheriff’s Deputy Jason Kinch all face racketeering charges in state court.

They were arrested in April after questions surfaced in the drug case against Mark Knight’s younger brother, Bryan Knight.

Investigators have given few details about a motive, but Bryan Knight alleges in a federal lawsuit filed earlier this year that his brother was trying to force him to give up a majority of his ownership interest in the family business, one of the largest oil and gas service companies in Acadiana.

Bryan Knight had questioned Mark Knight’s “lavish and uncontrolled spending for his personal benefit” when the older brother became CEO following the death of their father and Knight Oil Tools founder, Eddy Knight, in 2002, according to the lawsuit.

Investigators said Manuel — characterized as Mark Knight’s “henchman” — hid cocaine, painkillers and methadone in containers attached to magnetic strips on the underside of Bryan Knight’s car while the two brothers met in a June 2014 mediation session concerning ownership of Knight Oil Tools.

Bryan Knight was arrested leaving the meeting after Manuel called in a tip to local police about illegal drugs in his car.

Bryan Knight says in his federal lawsuit that after the arrest, his older brother “told him he could take care of the charges” if the younger brother cooperated with him.

Prosecutors eventually dropped the drug charges and focused their attention instead on Mark Knight.

Jackson and Kinch, the two law enforcement officers, allegedly worked with Manuel and Mark Knight to frame Bryan Knight in exchange for cash and gifts, police have said.

Both of the officers have been fired.

Manuel is accused of helping oversee the plot and threatening another Knight Oil Tools employee who had learned about it.

Manuel was laid off in March.

Mark Knight stepped down from the CEO job in December and resigned his position as chairman of the board on April 17, a few days after his arrest.

Mark Knight, Manuel, Kinch and Jackson face up to 50 years in prison if convicted.

Follow Richard Burgess on Twitter, @rbb100.