A Delta Air Lines pilot was arrested after officers at Minneapolis-St. Paul International Airport smelled alcohol on his breath before his California-bound flight Tuesday morning.

The pilot was going through the Known Crewmember entrance and tried to leave the line when he saw additional screening, according to a report from airport police.

The pilot was later found to be in possession of an “alcoholic container” and was suspected to be impaired, the report said.

The Transportation Security Administration “routinely includes random changes in its processes as an added layer of security — it helps prevent people from gaming the security system,” said airport spokesman Patrick Hogan.

Hogan said the pilot had been scheduled to fly DL1728 to San Diego.

The pilot, who lives in Rosemount, was arrested shortly after 11 a.m. in Terminal 1. He was released about three hours later, the report said, pending a formal complaint. The Star Tribune generally does not name suspects who have not been charged.

“The case is still under investigation and we are awaiting final toxicology results, so a detailed report is not available at this time,” Hogan said in an e-mail Tuesday evening.

Minnesota has a 0.04 % legal limit for pilots, according to Hogan. In addition, the Federal Aviation Administration also prohibits any pilot from flying within eight hours of drinking alcohol, what the agency calls “bottle to throttle.”

In a brochure aimed at pilots titled “Alcohol and Flying: A Deadly Combination,” the agency touches several times on the perils of drinking the previous day or evening and then waking up and climbing in the cockpit, even if it has been more than eight hours since that last drink.

One of the most notorious cases of drinking and flying occurred in 1990, when a Northwest Airlines captain, flight engineer and first officer were arrested when their flight from Fargo landed at the Twin Cities airport. A patron of a Fargo-area bar had tipped authorities that the crew had been drinking heavily there the night before. Federal regulations were tightened after that.