JEFFERSON COUNTY, Colo. (KDVR) — A father of one of the suspects arrested in the deadly rock-throwing crime spree was also arrested during the investigation for obstruction.

Mark Edwin Koenig, the father of suspect Joseph Koenig, was arrested on Tuesday when investigators showed up at his house to speak with his son. Joseph Koenig was arrested in connection to the death of 20-year-old Alexa Bartell who was killed when a rock hit her while she was driving in Jefferson County.

According to the arrest affidavit, Jefferson County Sheriff’s Office investigators went to a home in Arvada on Tuesday night to detain a homicide suspect.

When investigators arrived at the home, they spoke with Mark Koenig and asked if his son was home, to which he said “yes.” Investigators told Mark Koenig that they had some questions for his son and to call him to the front door.

Since Joseph Koenig is 18 years old, he agreed to speak with the sheriff’s office. His father went inside his home while they talked.

According to the affidavit, the father came back outside a few minutes later and told investigators that he did not want his son going anywhere that night and asked if the interview could be done the next day. One of the investigators responded and said that Joseph Koenig was needed that night.

Allegedly, Mark Koenig said that was not going to happen and was told by an investigator to walk toward the street while JCSO used a warrant to search his house.

According to the affidavit, the father asked, “You are going to do what?”

At that time, investigators said they attempted to control his arm but he was able to pull away and went to go back inside his home.

Deputies were able to control Mark Koenig and pull him away from the doorway and place him under custody, according to the affidavit.

He was charged with obstructing a peace officer.

Joseph Koenig faces a first-degree murder – extreme indifference charge for his alleged role in a crime spree that involved seven victims.