Police gave the all-clear at Norwalk High School after students were evacuated due to a reported bomb threat that police later determined to be a hoax.

Police say they were called to the threat of a bomb at Norwalk High School at 9:30 a.m.

"Norwalk Police officers are on scene at Norwalk High School and PTECH. We are checking an alleged threat, while staff and students are safely evacuated outside. Updates to come," police wrote in a tweet.

Police say they secured the school perimeter, while additional Norwalk police officers and K-9 bomb detection teams from Norwalk and Westport police department swept the area. 

Police say they entered the school and methodically checked for any suspicious items. 

Investigators cleared the school at 10:49 a.m., and say the school was found to be safe.

The bomb threat has been classified as a hoax, and staff and students were permitted to return to the building.