Knight Oil Tools announced Thursday that it has started a search for a board chairman, a position left vacant after former Chairman Mark Knight’s recent arrest on suspicion he tried to frame his brother in a drug bust last year.

Meanwhile, Lafayette Parish investigators have wrapped up the investigation into Knight and three other men in the alleged scheme.

Sheriff’s Capt. Kip Judice said the case will be handed over to the District Attorney’s Office by Monday.

In an emailed release, Knight Oil Tools said its search for a chairman “is one of the most important decisions we’ll make as a team and our pursuit to find the right individual is the highest priority. This short transition period is having no effect on business operations.”

Mark Knight surrendered to authorities on April 14 following an investigation by the Sheriff’s Office and State Police.

The agencies accused Knight of getting a Knight Oil employee to plant cocaine and prescription pills on the underside of Bryan Knight’s vehicle on June 4.

Mark Knight was arrested on one count of racketeering and released after posting bail of $100,000.

Two law enforcement officers also were implicated. State Trooper Corey Jackson and sheriff’s Deputy Jason Kinch are accused of taking money and gifts in exchange for their input in the scheme. Jackson and Kinch were arrested the weekend of April 11 on one count each of racketeering. Like Mark Knight, each had to post bail of $100,000 before he was released.

The fourth suspect, former Knight Oil employee Russell Manuel, arranged the setup, according to investigators.

Manuel was booked April 17 on counts of criminal conspiracy, possession of cocaine, possession of Lortab, possession of methadone, extortion and intimidating a witness. Manuel also posted $100,000 bail.

In the arrest report, lead investigator Judice describes Manuel as Mark Knight’s “henchman” who did the heavy lifting in Knight’s plan to set up his only brother on drug charges. Bryan Knight was involved in a mediation with family members over the finances of the business.

Bryan Knight was arrested after someone — detectives believe it was Manuel — called in a tip to narcotics officers that Knight had cocaine and prescription pills. However, prosecutors with the District Attorney’s Office declined to charge Knight.

Knight Oil Tools was started 43 years ago by Mark and Bryan Knight’s father, Eddy Knight. It is privately held, has more than 900 employees and is one of the largest rental tools companies in the oil and gas industry.

In an April 17 statement in the employee newsletter, Knight Oil Tools announced that Mark Knight had resigned as chairman and as a director in the company. That resignation followed news that Knight in December had relinquished his titles of president and chief executive officer. The company has not said why Knight stepped down from those positions.

“While recent reports in the news are difficult for members of our team and leadership, they have not and will not affect corporate operations,” Knight Oil Tools says in the newsletter. “This is an unfortunate situation.

“We are working directly with law enforcement officials and hope for a full resolution,” the company said.