Police on Tuesday released a 16-year-old boy who was arrested on suspicion of having a role in a shooting last week at a Richfield High School football game that left two people wounded, the Hennepin County Attorney's Office said.

A 15-year-old boy, a Richfield student who was arrested on accusations of being the shooter, remained in custody awaiting charges that could come as soon as Wednesday, said Maxwell Page, spokesman for the county attorney.

The older teenager, who lives in Edina, "has been released pending further investigation," Page said early Tuesday afternoon. He was accused of instigating a conflict outside the football facility.

"We have received an extension [from the court] to hold the other juvenile for another 24 hours," Page said.

Officials have yet to disclose a motive for the shooting, which left victims 18 and 21 years old with leg wounds.

On Monday, school administrators called off secondary school classes after unspecified online threats received early in the morning, a decision made "due to the timing and the recent events outside our homecoming game," Superintendent Steven Unowsky said in an announcement.

The district did not disclose the nature of the threats or where they originated, and classes resumed Tuesday morning at the middle school and high school, the Richfield College Experience Program and a program in the South Education Center.

Richfield Mayor Maria Regan Gonzalez released a statement Tuesday that said "our community has been experiencing a range of emotions, from heartbreak and overwhelm to fear and confusion. But into that fear and confusion we have also received an outpouring of love and support for our families and students."

The mayor added, "There is movement underway, both in the short-term and long-term, to work together to find tangible ways to ensure that our families and students feel safe and supported in their schools and in their city."