WASHINGTON, May 8 (Reuters) - The National Highway

Traffic Safety Administration said Friday it is opening an

investigation in a series of crashes of start-up Avride

autonomous vehicles that raised questions about the competency

of the vehicles.

NHTSA said the vehicles' performance may indicate

inappropriate assertiveness and insufficient competence "and may

also constitute traffic safety violations", and added some

crashes resulted in property damage and one reported minor

injury.

NHTSA noted that Avride is operating some of its AVs on the

Uber ( UBER ) platform and has offered passenger service to the

public since December in Dallas, where many of the crashes

occurred.