Small town mayor shoots and kills three men after one 'forced himself on his wife and exposed his genitals' in Memorial Day rampage

A former law enforcement officer who served as the mayor of a small South Dakota town has been charged in the killings of three people. 

Jay Ostrem, 64, was jailed on $1 million cash-only bond on three counts of first-degree murder, South Dakota Attorney General Marty Jackley said.

A probable cause affidavit identified the victims as two brothers Paul Frankus, 26, and his 21-year-old brother Zach and Timothy Richmond, 35.

Ostrem worked in law enforcement for more than two decades in Wyoming and South Dakota. 

A former law enforcement officer and mayor of Centerville Jay Ostrem, 64, was jailed on $1 million cash-only bond on three counts of first-degree murder

Paul Frankus, 26, left, and his 21-year-old brother Zach, right, were both shot dead

He served as mayor of Centerville, a tiny town of less than 1,000 people, some 40 miles south of Sioux Falls, about a decade-and-a-half ago, but the exact dates weren't immediately available.

The probable cause document said a man in Centerville, identifying himself as Zach Frankus, called police at 9:44pm on Monday night to report that his brother had been shot by 'a guy from across the street' and that the shooter had gone back home. 

Frankus was still on the phone with a dispatcher when he said that he had been shot, too. He was described as 'frantic'. Frankus then stopped talking, charging documents state.

Authorities raced to the scene, where a Game Fish and Parks officer saw Ostrem leaving the home identified as the scene of the shooting. 

The home in Centerville, South Dakota where a triple homicide took place on Monday nght

The former Centerville mayor has been charged with the triple murder in the case

Authorities raced to the scene, where a Game Fish and Parks officer saw Ostrem leaving the home identified as the scene of the shooting, pictured above

Officers visited the home where the call originated, above, and found all three victims

Ostrem initially ignored commands to stop before laying down on the ground. He was arrested a short time later.

An AR-style rifle was on the ground near him, and he had a handgun in his pocket.

Police noted how Ostrem was bleeding from his left hand and that he smelled of alcohol. 

Officers then went to the home where the call originated and found all three victims.

Ostrem's wife, who is British, told police that a neighbor, Paul Frankus had sexually assaulted her on Thursday, and she told Ostrem about the assault Monday night. 

Jay Ostrem is pictured in 2009 when he worked as the Turner County Sheriff Investigator

The pair had been drinking together when he forcibly kissed her, exposed his genitals and pressed himself against her, reports the Argus Leader. 

She said Ostrem 'got up and went raging out of the house,' according to the document.

She explained to officers how her husband did not tell her where he was going and that he didn't leave armed, although weapons were kept in the home and he likely had some in his car.  

Ostrem was booked on Tuesday morning into the Minnehaha County Jail in connection with the Centerville shootings.

The Centerville, South Dakota home where a triple murder took place on Monday night is seen roped off

The home of the former mayor and law enforcement officer 

'Jay Ostrem has been arrested and charged with three counts of first degree murder, and law enforcement has secured the scene,' Attorney General Jackley stated in a news release. 

'There is no further threat to the public.' 

Ostrem initial appearance is scheduled for 3pm on Wednesday.