Authorities responded to a reported hazmat situation at Disneyland on Tuesday after a strong unknown odor was detected near the backstage area of Tomorrowland’s Star Tours attraction.

Sgt. Mark Sutter of the Anaheim Police Department told KTLA that officers responded to an “unknown odor near Star Tours backstage” around 12:30 p.m.

According to Disneyland officials, building materials being used by a contractor caused a reaction in a backstage area. Several cast members were treated on site by paramedics and released.

Authorities responded to a reported hazmat situation at Disneyland on Tuesday after a strong unknown odor was detected near the backstage area of Tomorrowland’s Star Tours attraction.

Sgt. Mark Sutter of the Anaheim Police Department told KTLA that officers responded to an “unknown odor near Star Tours backstage” around 12:30 p.m.

According to Disneyland officials, building materials being used by a contractor caused a reaction in a backstage area. Several cast members were treated on site by paramedics and released.

A large portion of the Tomorrowland area, including several attractions, was shut down as authorities investigated the hazardous materials incident. The area was later reopened to guests on Tuesday night.

No guests have reported symptoms or been affected so far, according to police.