Three people were killed in a small town in South Dakota. The suspect is the former mayor

The emergency call was received at 9:44 p.m. on Monday, May 27, via the emergency services of the small county in South Dakota.

The man, who identified himself as Zach Frankus, told police that their neighbor shot his brother with a shotgun.

Then, still on the phone, he said he had been shot.

“Shortly after reporting that he had been shot, the man lost communication with dispatch,” Special Agent Jon Basche of the South Dakota Department of Criminal Investigation later wrote in a probable cause affidavit obtained by PEOPLE.

When investigators arrived at 1031 Main Street in Centerville, SD, an officer observed a man leaving the home.

Police later identified the man as the city’s former mayor, Jay Edward Ostrem. The 64-year-old also worked as a sheriff’s investigator in Turner County, where he is now charged with murder.

When Ostrem was stopped by a police officer that night, he told the officer that he “had a gun in his pocket,” according to the arrest affidavit.

Investigators seized the pistol and said they found an automatic rifle on the ground nearby in his possession, as well as “spent shotgun shell casings and at least one spent rifle cartridge.”

According to the affidavit, the arresting officer said that the former politician smelled of alcohol.

Three dead men were found in the house.

According to the complaint obtained by PEOPLE, Ostrem is charged with three counts of premeditated murder of Zachary Ryan Frankus (21) and his brother Paul Wyland Frankus (26), as well as Timothy E. Richmond (35).

Just a few houses down, at 1100 Main Street, investigators found a female Ostrem family member at home, according to the affidavit.

The family member told investigators that on Thursday, May 23, one of the neighbors came over while the former mayor was sleeping and the two were drinking alcohol. According to the affidavit, she told police that the man sexually assaulted her.

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She also told investigators that she had told the former mayor about the alleged assault earlier that evening and that, according to the affidavit, he “got up and walked out of the house angry.”

According to the affidavit, she told officers that he did not say anything to her as he left and that she did not know where he went or if he was armed when he left the house.

She pointed out that the former mayor had previously worked in the police force and said he had weapons in his home and “possibly in his vehicle,” according to the affidavit.

Tony Mangan of the South Dakota Attorney General’s Office confirmed to PEOPLE that Ostrem has been held on $1 million cash bail since Tuesday, May 28.

His online Minnehaha County Jail roster shows the former mayor was booked into the facility at 7:09 a.m. Tuesday with inmate number 2519480. His online records show he is being held without bail.

The Turner County, South Dakota, Clerk of Court confirmed to PEOPLE that Ostrem’s first court appearance is scheduled for May 28 at 4 p.m. CDT at the Clay County Courthouse in the mall town of Vermillion, South Dakota.

At the time of the call, he had no defense attorney on his list.