Two high schools were evacuated in Hamilton Monday after threats were made to staff and students at both places.

As of around 2 p.m. Monday, students and staff were cleared to return to Ancaster High School. St. Mary Catholic Secondary School remained under evacuation in west Hamilton.

Police have confirmed that St. Mary's was a bomb threat, but haven't said what specific threat the Ancaster incident was.

Ancaster students were evacuated to Firestone Arena and Community Centre and returned to school in the afternoon, the Hamilton-Wentworth District School Board said in a tweet.

St. Mary's closed for the day. The board posted to the school website that the school was cleared by police and it will be open as usual on Tuesday.

The St. Mary's threat was just after 10 a.m. The Ancaster incident happened just after 12:30 p.m.

Police said they're still investigating to determine whether the incidents are connected.

HPS investigating bomb threat at St Mary's School. All students evacuated & safe. Please stay away from the area. Police are currently searching the building. <a href="https://twitter.com/hashtag/HamOnt?src=hash&ref_src=twsrc%5Etfw">#HamOnt</a> —@HamiltonPolice