WASHINGTON, July 29 (Xinhua) -- Three people died and one person was critically injured in a car crash in New Hampshire, U.S., state police said Sunday.

Police said the crash may have happened on Saturday evening, but was reported only Sunday after a pedestrian discovered the wreckage in dense vegetation.

The passengers were in their late teens or early 20s. Speeding is suspected to be a cause of the crash as the car veered off the road at a curve, according to police.

Over 70 people have been killed in highway accidents in the state this year, representing a significant rise from last year, according to state highway officials.