Authorities in New Mexico are trying to figure out the circumstances that led to a hot air balloon crash that killed five people in Albuquerque.

It happened just after 7am Saturday. The hot air balloon hit a power line about six miles west of the Albuquerque airport and caught fire. The basket carrying the passengers was separated from the envelope, which is the balloon, and fell 100 feet to the street below.

The envelope came down in a nearby neighborhood.

Four people were declared dead on the scene. According to an ABC News report, police say the victims ranged in age from their 40s to their 60s. Three of the people onboard, including the pilot, were men, two were women. One man who initially survived the fall and was taken to the hospital, later died.

“The balloon hit the top wires — the gondola of the balloon skirted along the top wire, caught on fire and crashed into the intersection,” Albuquerque Police Dept. spokesman Gilbert Gallegos told CNN.

The National Transportation Safety Board (NTSB) is on site to investigate what happened and why the balloon hit the electrical wires.