LAS VEGAS (AP) — Federal transportation officials will investigate the crash that involved a driverless shuttle bus in Las Vegas.

The National Transportation Safety Board on Thursday said a team of four officials is expected to arrive in Las Vegas Friday.

The crash between the self-operating bus and a semi-truck happened Wednesday, less than two hours after the driverless vehicle debuted. No injuries were reported.

Police in Las Vegas have said the driver of the semi-truck was cited for illegal backing. Authorities have said one of the semi-truck's tires tapped the front bumper of the bus.

The oval-shaped shuttle that can transport up to 12 passengers has an attendant and computer monitor, but no steering wheel and no brake pedals. It uses GPS, electronic curb sensors and other technology to make its way.