The principal of a Regina Christian school ended a tense standoff with a gunman Tuesday, when he noticed the weapon was a pellet pistol and wrestled it from the suspect's hands.

Frightened students rushed out of the building when the suspect threatened the pastor of Luther College and demanded he read aloud a letter.

The principal, Mark Anderson, told reporters he kept talking to the suspect and moving closer to him, until he saw the weapon was not a real gun.

"It was not the kind of firearm I thought it was," he said. "Indeed, it was less serious than that, so I tried to take away from him. We wrestled over it for a couple seconds, and at that point the SWAT team came in and took control of the situation."

A 16-year-old boy was later taken into custody.

Video of the incident, submitted to CTV's MyNews, shows the suspect waving the pellet gun and pointing it at students and staff.

Lara Guzik Rostad, with the Regina Police Service, said there were "no indications of injuries" to anyone.

She said police received a call around 10:20 a.m. local time reporting "a male youth with a firearm at the school."

Heavily-armed officers entered the building and began a room-by-room search. Students, many in tears, ran outside where a crowd of anxious parents had gathered.

"At approximately 11 a.m., we had one male in custody and at that point attempted to evacuate the school," Rostad told CTV Newsnet.

CTV reporter J.C. Garden said the male in custody was reportedly a former student who had been kicked out of the school.

"He was there apparently wearing a blonde wig. He had what looked to be a gun that was hidden in camouflage," said Garden. "He was waving it around and yelling profanities."

Luther College was founded in the early 1900s, and has both a high school campus and a university campus.

The incident happened on the same day a gunman in Finland killed 10 people before shooting himself in the head. The 22-year-old had left threatening handwritten notes, along with a violent YouTube posting, and had been interviewed by police as recently as Monday.