A Minnesota state trooper was clocked driving at least 94 miles per hour in a 55 mph zone in his squad car near Fergus Falls, Minn., and charged by summons nearly two months later with speeding, authorities said Monday.

Sgt. Jesse Grabow, a 17-year veteran of the State Patrol and the agency's lead spokesman for western Minnesota and the St. Cloud area, was charged Friday in Otter Tail County in connection with the alleged offense on April 28.

"As state troopers, we are not immune to the dangers of exceeding the speed limit," Col. Matt Langer, chief of the State Patrol, said in a statement. "[The sergeant] erred in judgment and broke the law when he was observed speeding on duty without cause. We take this very seriously and have initiated an internal affairs investigation now that the city attorney has completed his review."

Grabow, 38, remains active on the force but will have his duties as a spokesman handled by other troopers for the time being, Langer said.

Telephone and e-mail messages were left with Grabow seeking his reaction to the charge, which carries upon conviction a fine of up to $300 plus a $150 surcharge, because he's accused of exceeding the speed limit by at least 31 mph.

According to the criminal complaint filed by the Fergus Falls city attorney's office:

About 6:45 a.m., 30 minutes or so after sunrise, trooper Robyn J. Birr was heading west on Hwy. 210 and saw a car heading east that appeared to be speeding. The trooper's radar recorded the car at 95 mph and 94 mph.

Birr activated her emergency lights, then turned them off after seeing that it was a trooper vehicle. Grabow sent a message to Birr after they had passed each other on Hwy. 210. The complaint does not say what the message contained, and Assistant City Attorney Joseph Ellig declined Monday to disclose its contents.

Birr pulled over and determined that Grabow's was the only patrol vehicle nearby.

Ellig said the trooper did not pursue Grabow in an attempt to have him slow down or issue him a citation.

"Why Trooper Birr didn't pull him over, I don't know," Ellig said. "That's a question for law enforcement."

The State Patrol declined Monday to address Birr's decision to not pursue Grabow. "The entire incident, including the sequence of events, will be reviewed as part of the internal affairs investigation," said Lt. Tiffani Nielson, the patrol's chief spokeswoman.

Explaining why Grabow was not charged for two months, Ellig said the patrol's case first went to the county attorney's office, which saw it as a conflict of interest because of the amount of work it does with the patrol.

Ellig said that he learned about the case roughly three weeks ago and that it came to him a week or so before he filed the complaint on Friday.

Grabow's professional file includes a lifesaving award in 2012. Grabow and a passerby saved a woman who had a seizure, which caused her car to plunge into Lake Latoka near Alexandria, Minn. He hasn't had any disciplinary actions or formal complaints.