14-year-old suspect dead after active shooter reported outside Wisconsin middle school: Sources

A 14-year-old suspect is dead following a confrontation with police Wednesday after an active shooter was reported outside a Wisconsin middle school, sources told ABC News.

The teen had approached Mount Horeb Middle School with what appeared to be a long gun, the sources said.

The suspect was a male student in the Mount Horeb Area School District, according to Wisconsin Attorney General Josh Kaul. A vehicle associated with the suspect was being searched for evidence by bomb technicians, according to sources.

Officers from the Mount Horeb Police Department responded to a report of an "individual with a weapon outside the middle school" and used deadly force, Kaul said during a press briefing Wednesday evening.

The school district said police responded to help "scope out" an active shooter at the school and the threat was "neutralized" outside the building. No injuries have been reported among students and staff, it said.

"The individual did not breach [the] entryway," the district said on Facebook.

Kaul was unable to confirm whether any shots were fired by the suspect, telling reporters he is limited in what details can be shared at this time due to the ongoing investigation.

No additional suspects have been located following an initial search of the middle school and all students and staff are safe, the district said. Law enforcement continues to "vigorously investigate" the incident though there is not believed to be an ongoing threat to public safety at this time, Kaul said.

The Wisconsin Department of Justice's Division of Criminal Investigation is leading the investigation into the "entirety of the incident," Kaul said. Some Mount Horeb police officers are on leave, per standard practice in a use-of-force incident, he said.

All school district buildings went into lockdown around 11:15 a.m. local time, the district said. School officials advised that students were to remain inside amid the police investigation and be dismissed pending police approval. The district has since started to release some students.

A decision on the full return to school is expected soon, with the hope to resume classes by Friday, according to Mount Horeb School District Superintendent Steve Salerno.

"If there's a story to be told of today, it's a story of an amazing staff that have rallied in support of our beautiful children," Salerno said during the press briefing Wednesday.

He said proactive safety measures, including the installation of security enhancements such as vestibules and locked front doors, were crucial in preventing a worse outcome.

"This could have been a far worse tragedy," Salerno said.

The FBI was on the scene and assisting state and local partners, an agency spokesperson confirmed to ABC News.

Officials for the village of Mount Horeb, located about 20 miles southwest of Madison, said the community faced a "horrifying situation" Wednesday while commending the "swift and courageous" response by the school district and emergency personnel to the active shooter incident.

"Due to safety precautions taken by our Schools, the shooter was never able to enter the building," Mount Horeb Village president Ryan Czyzewski and Mount Horeb Chamber Board chair Kara Brandemuehl said in a joint statement. "The collaboration and coordination between our community's first responders and School District exemplified the highest standards of professionalism and dedication."

Wisconsin Gov. Tony Evers said he is "closely monitoring" the situation.

"Every day, our kids, educators, and staff go to school and hope a day like this will never come," he said in a statement.

Evers said he has extended his full support to the school community "as they grapple with what has undoubtedly been a scary and traumatic day for everyone involved."