A 15-year-old boy was charged Wednesday in the shooting of two people at Richfield High School's homecoming football game last weekend.

The Richfield High student was one of two teenagers arrested over the weekend in connection with Friday night's shooting during a confrontation among several people outside the football facility. Two men, ages 18 and 21, suffered leg wounds.

Investigators said in a separate court filing Tuesday that the defendant has had prior unspecified "police contacts" and was involved in an altercation with one of the shooting victims this month at a fast-food restaurant.

The teen remains in custody. His mother declined Wednesday afternoon to discuss the allegations other than to say her son has an attorney.

The other suspect, an Edina 16-year-old who was accused of instigating the altercation, was released from custody Tuesday without charges.

Hennepin County Attorney Mike Freeman said in a statement that because of the defendant's age, "Minnesota law treats this case as nonpublic. [Therefore], we will not be offering further comment as to this juvenile's case."

Freeman said the case remains under investigation and "we are working closely with law enforcement as we consider additional charges."

The County Attorney's Office declined to specify what the 15-year-old is charged with or whether prosecutors would attempt to move the case to adult court, where any potential sentence would be more severe should the teen be convicted.

While Freeman's office could not say anything more about the case, police laid out details in a search warrant affidavit filed Tuesday in Hennepin County District Court.

In the seven-page filing, police asked to be allowed to search an apartment in Bloomington, where investigators say they believe the shooter may have left incriminating evidence.

According to the document, which is based on police interviews:

The 21-year-old victim said that when he saw several young people running toward the Bloomington Kennedy seating area Friday night, he decided to get closer in hopes of preventing a fight.

He said the 16-year-old, wearing a ski mask, instigated a fight with him. The younger teen, dressed entirely in black and also wearing a mask, shot both victims with a handgun equipped with an extended magazine. Witnesses identified the shooter to police.

The wounded 18-year-old said he recognized the shooter "from an altercation that took place a couple weeks prior, [when] he was assaulted by a group of individuals" at a Chipotle restaurant.. He said members of the 15-year-old's group had been threatening him through fake social media accounts.

As the 15-year-old's family members were being interviewed by police at their home Sunday, they received phone calls from the boy. The calls were traced to a Bloomington apartment building, and police asked permission to search one of its units, where the shooter "could have hidden evidence."

The 15-year-old was arrested later that evening at his home.

The day after his arrest, district administrators called off secondary school classes because of unspecified online threats received early in the morning.

The decision was 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 their origins, and classes resumed Tuesday morning at the middle school, high school, the Richfield College Experience Program and a program in the South Education Center.