April 29 (Reuters) - The U.S. auto regulator said on

Monday it has opened a preliminary investigation into Ford

Motor's ( F ) hands-free driving technology BlueCruise after

being informed of two incidents involving Mustang Mach-E cars

that collided with stationary vehicles.

The National Highway Traffic Safety Administration's Office

of Defects Investigation (ODI) opened the evaluation to

investigate BlueCruise, which provides partial driving

automation with the expectation that the driver actively

supervises its performance.

Both the collisions occurred during "nighttime lighting

conditions", and each resulted in at least one fatality,

according to the NHTSA.

ODI's initial investigation of the incidents confirmed

BlueCruise's engagement in each of the vehicles right before the

collision.

BlueCruise is only available on certain roadways and uses a

camera-based driver monitoring system to determine driver

attentiveness.

The investigation will evaluate the system's performance on

the dynamic driving task and driver monitoring, the NHTSA said.

Ford Motor ( F ) did not immediately respond to a request for

comment.