Longtime Lafayette Airport Director Greg Roberts resigned Sunday after being placed on administrative leave for an incident that occurred last week, officials said.

“We wish Greg the best and are disappointed (that) what appears to be a momentary lack in judgment has impacted a 21-year career at Lafayette Regional Airport,” Lafayette Airport Commission Chairman Matt Cruse said in a prepared statement.

Cruse said Roberts will be replaced temporarily by the airport’s deputy director, Mike Burrows, as the commission looks nationally for another director.

The Lafayette Parish Sheriff’s Office is investigating the incident, Cruse said.

Cruse would not elaborate on what Roberts did and directed further questions to airport commission attorney Todd Schwartzendruber, who also did not comment.

A female who answered the phone at Roberts’ home said Monday he wasn’t taking calls from the media. And a message left on Roberts’ cellphone was not returned.

At a news conference at the airport Monday, Cruse said the incident that led to Roberts’ resignation took place Wednesday afternoon and involved at least one other another airport employee and at least one contractor.

Though he would not say exactly what happened, Cruse said the transgression was not physical or sexual, and that no one was hurt.

“It’s more along the lines of conduct,” Cruse said.

Cruse said he learned of the incident on Friday and immediately appointed a committee of three airport commission members to investigate the matter.

The committee met with those involved and also called the Sheriff’s Office, which sent an investigator. Sheriff’s Capt. Craig Stansbury said the detective looking into the matter has not yet completed a report. Stansbury said he could not comment further.

On Friday, Cruse placed Roberts on administrative leave. On Sunday, Roberts gave Cruse a letter that announced his retirement.

“Greg from the very beginning has been cooperative, sincere and apologetic,” Cruse said Monday.

Attending the news conference Monday were airport commissioners Paul Guilbeau Sr., Paul Segura, Timothy Skinner and Carroll B. Robicheaux Jr.

News of the resignation came the day before the Lafayette City-Parish Council officially votes to send an election tax to voters later this year.

In April, the council made the decision to allow voters to decide the fate of a 1-cent sales tax to be levied for eight months in 2015 to pay for a new airport terminal.

Tuesday night the council is expected to formally approve the measure.