Scroll through the media gallery above to see video and images from Carroll University, courtesy TODAY'S TMJ4, Newsradio 620 WTMJ's Jodi Becker and a student at the school.
WAUKESHA - Chopper 4 shows a man taken into custody after officials locked down the Carroll University campus in Waukesha following a report of a man with a firearm.
The lockdown was lifted just after 12:00 p.m. Tuesday.
TODAY'S TMJ4 video showed a possible suspect near the scene being taken into custody at that time.
Waukesha Police Spokesman Ron Oremus said they "believe with pretty high confidence" that he was the reported gunman.
Oremus said the weapon recovered at the man's home was "some sort of non-lethal weapon, I believe an air-soft gun, not a shotgun, not a rifle, not a firearm at all except by appearance."
He also said Waukesha has an ordinance prohibiting shooting air-soft guns in public.
Waukesha Central Middle School, Saratoga Middle School, Randall Elementary, Whittier Elementary School and Waukesha's District Offices were placed on lockdown as well.
TODAY'S TMJ4's Jermont Terry reports that parents of Waukesha Catholic Memorial High School also received word that the their school was on lockdown. The school did not initially confirm that report.
At about 11:25 a.m., police with guns drawn had closed off Maple Street near the campus, according to TODAY'S TMJ4's Todd Hicks. It was believed the gunman may live near that location.
The school halted classes for the remainder of Tuesday, and asked students off campus not to come to the university.
Carroll University's spokesperson told Newsradio 620 WTMJ's Michelle Richards that two students spotted the gunman with what was described as a long gun. The spokesperson said he is white.
TODAY'S TMJ4's Jessie Garcia teaches a class on the campus, and Newsradio 620 WTMJ's Jodi Becker was assisting in a class there Tuesday morning.
They both say the text notification went to students' phones, which Jessie says she received as well.
This was the text that came to students at 10:39 a.m.:
"Text from Carroll:: Not a test There is a report of a male with a firearm walking near the tennis courts and the Barstow Building on Barstow. remain indoors until further notice"
The gunman was reportedly in his 50's, wearing a brown jacket and black hat last seen walking west from Barstow Street toward Grand.
A second text message came to students at 11:09 a.m. with that description.
Jessie says all of the buildings were being locked. Students within her class were remaining as calm as possible.
Jodi said that students were having trouble communicating with parents due to the cement walls inside many of the Carroll University buildings.
Oremus said that a number of K-9 units, Waukesha Sheriff's deputies and police from Menomonee Falls to assist.
Jodi Becker, Jessie Garcia, Todd Hicks and Jermont Terry contributed to this story.