PONTIAC, Mich. (NewsNation Now) — The parents of the teenage suspect in the Oxford High School shooting were arrested overnight in Detroit, police confirmed to NewsNation. The couple pleaded not guilty Saturday to involuntary manslaughter charges.

Judge Julie Nicholson assigned bond of $500,000 apiece to each of the parents and placed other requirements such as GPS monitoring, agreeing with prosecutors that they posed a flight risk.

The Oakland County Sheriff’s Office said the Detroit Police Department found Jennifer and James Crumbley in an “industrial building” that housed artwork a few blocks inland from the Detroit River.

“This isn’t indicative of turning yourself in — hiding in a warehouse,” White said.

White said the couple “were aided in getting into the building,” and that a person who helped them may also face charges.

Michigan police issued an alert asking for help locating the couple on Friday after they were charged with four counts of involuntary manslaughter in connection with the attack.

Their son, Ethan Crumbley, 15, is accused of killing four classmates and injuring seven other people during a shooting Tuesday.

The parents’ attorney promised Oakland County Sheriff Michael Bouchard they would surrender to authorities if they were charged, according to a news release. But Bouchard said the lawyer told him Friday she was not able to reach them.

The parents’ attorneys, Shannon Smith and Mariell Lehman, contended that the Crumbleys intend to turn themselves in, and Smith and Lehman released the following statement on Friday afternoon.

“On Thursday night we contacted the Oakland County prosecutor to discuss this matter and to advise her that James and Jennifer Crumbley would be turning themselves in to be arraigned. Instead of communicating with us, the prosecutor held a press conference to announce charges.”

“The Crumbleys left town on the night of the tragic shooting for their own safety. They are returning to the area to be arraigned. They are not fleeing from law enforcement despite recent comments in media reports.”

Late Friday, U.S. Marshals announced a reward of up to $10,000 and asked for the public’s help in locating the couple. It’s unclear if anyone is eligible for that reward.

Bouchard, however, held that the parents were missing. He also said he believed Michigan prosecutor Karen McDonald made a mistake when she told reporters earlier this week she was considering charging the parents.

“I’ve been sheriff for 21 years, and I’ve never had anyone have a press conference announcing charges before we had the opportunity to have somebody in custody,” Bouchard said on “NewsNation Prime” on Friday.

He added if he’d known the charges were coming today, his office would have been “more proactive” to apprehend the parents. In a news release Friday afternoon, Bouchard said federal and local agents were looking for the Crumbleys.

“The action of fleeing and ignoring their attorney certainly adds weight to the charges,” Bouchard said in the release. “They cannot run from their part in this tragedy.”

The parents’ role in the shooting became a focal point in the investigation. On Wednesday, Bouchard told reporters he learned the parents were in meetings with school administrators about their son’s behavior the day before and the day of the shooting.

On Friday, McDonald said the parents were summoned a few hours before the shooting after a teacher found a drawing of a gun, a person bleeding and the words “help me.” Ethan Crumbley was returned to his classroom and later emerged from a washroom, firing a gun at students in the hallway.

McDonald said the semi-automatic gun used in the shootings was purchased by James Crumbley last week and given to the teen.

McDonald said Jennifer Crumbley sent her son a text, saying “Ethan, don’t do it.”

Jennifer and James Crumbley were charged with four counts of involuntary manslaughter. Under Michigan law, an involuntary manslaughter charge can be pursued if prosecutors believe someone contributed to a situation where harm or death was high. If convicted, they could face up to 15 years in prison.

Ethan Crumbley was charged as an adult with two dozen crimes, including murder, attempted murder and terrorism, for the shooting Tuesday at Oxford High School in Oakland County, roughly 30 miles north of Detroit.

Tate Myre, 16; Hana St. Juliana, 14; Madisyn Baldwin, 17; and Justin Shilling, 17 died during the rampage.

The superintendent for the district late Thursday posted a YouTube video in which he said the teenager was called to the office before the shooting but, “No discipline was warranted.”

Tim Throne, leader of Oxford Community Schools, said the high school looks like a “war zone” and won’t be ready for weeks. But he repeatedly credited students and staff for how they responded to the violence.

“To say that I am still in shock and numb is probably an understatement. These events that have occurred will not define us,” Throne, grim-faced and speaking slowly, said in the 12-minute video.

“I want you to know that there’s been a lot of talk about the student who was apprehended, that he was called up to the office and all that kind of stuff. No discipline was warranted,” Throne said. “There are no discipline records at the high school. Yes, this student did have contact with our front office, and, yes, his parents were on campus Nov. 30.”

Throne said he couldn’t immediately release additional details.

Bouchard said the community is still “absolutely numb” after the shooting, and said a call for medical help at a Friday vigil sparked a brief panic as some in the crowd believed further violence erupted.

“It breaks my heart because that’s just an example of how still terrified the community is of this incredible tragedy,” Bouchard said.

This is a developing story; check back for updates.

The Associated Press contributed to this report.