At least six schools in Alberta were closed today over what officials are calling potentially threatening situations.

A 17-year-old male is in custody after allegedly making threats at the high school in Ponoka.

Ponoka Composite High School was locked down today while RCMP looked for the offender. He was found at his home and arrested. Police also found two firearms — a .22 calibre and high-powered rifle — and ammunition.

Charges of uttering threats, unsafe storage of firearms and possession of weapons dangerous to public peace are pending against the teen.

Classes were cancelled at St. Dominic Catholic High School, West Central High School and Confluence Campus, a satellite campus of Red Deer College, in Rocky Mountain House because of a possible security threat.

The three schools share one campus.

RCMP have investigated and determined there is no immediate threat.

'Allegation appears unfounded'

"It is believed the comments made by the youth were construed over the course of a couple days," said Rocky Mountain House RCMP in a release. 

"Although the allegation appears unfounded, the investigation is continuing. The RCMP want to assure parents, students and staff that at no time the safety of all was at risk."

In Medicine Hat, Crescent Heights High School was closed as a precaution after an incident that the school is calling a low risk to students and staff.

At least one school in Devon, near Edmonton, also cancelled classes following a threat made online.

No one has been arrested in connection with those incidents.

The Alberta incidents come to light just one week after a mass shooting in Newtown, Conn. 

Twenty elementary school children and six staff members at Sandy Hook Elementary School were killed by a 20-year-old gunman, who then killed himself.