LOS ANGELES—Eight teenagers who were on a field trip to the La Brea Tar Pits became disoriented and were taken to hospitals May 14 after apparently ingesting cannabis edibles.

The problem was reported at about 12:45 p.m. by an on-site security guard at the museum in the 5800 block of West Wilshire Boulevard, according to the Los Angeles Fire Department.

The eight teens were found with “altered level of consciousness, following their reported ingestion of cannabis edibles,” Brian Humphrey of the LAFD said in a statement.

All of the teens were taken to hospitals by ambulance in fair condition, Mr. Humphrey said.

Los Angeles Police Department officers were sent to assist the LAFD in the investigation, police said.