A chopper carrying tourists on a luxury sunset tour of the Las Vegas Strip and the Hoover Dam crashed into a mountainside surrounding Lake Mead, killing the pilot and four passengers on board, reported Associated Press.

The National Park Service spokesman Andrew Munoz told AP that several witnesses heard the crash at around 5 p.m. and saw smoke emitting from a site, about 4 miles west of the lake’s edge.

The federal authorities have confirmed that all the four passengers who were reportedly on a local tour died in the collision. However, the identities of the victims have not been released.

The officials said that the investigation and recovery were delayed as the remote site of the incident is about 30 miles from Las Vegas and inaccessible by road.

The aircraft was operated by Sundance Helicopters for local tours over Lake Mead, the Hoover Dam and the Las Vegas Strip.

The Federal Aviation Administration spokesman lan Gregor told AP that the helicopter, built in 1989, was an AS-350 and could carry up to six passengers.