Enfield — Police say the driver of a pickup truck died and his three passengers suffered non-life-threatening injuries in a single-vehicle accident on Monday night on Interstate 89 northbound near Exit 14.

Police identified the driver as Kenneth Stone Jr., of Duxbury, Vt., and said the 36-year-old lost control of the 2008 GMC Sierra, causing it to overturn in the median, according to a New Hampshire State Police news release.

Medical personnel transported Stone to Dartmouth-Hitchcock Medical Center after the accident; Stone later died as a result of his injuries, according to police.

Colin William, 27, and 36-year-old Jessica Wright, both of Duxbury, Vt., were in the truck, along with a 14-year-old female passenger.

A DHMC spokesman said Wright has since been released from the hospital. The spokesman said he couldn’t release an update on William’s condition.

The young passenger’s condition also was unknown on Tuesday evening.

New Hampshire State Police still are investigating what caused Stone to enter the median around 7 p.m.

According to the release, Stone was towing a trailer with a car on it at the time of the accident.

When the truck overturned, Stone was ejected from the vehicle, the release said.

Sgt. Ron Taylor said he wasn’t aware of the relationship of the passengers to the driver.

One lane of the highway was closed for several hours on Monday night.

Anyone with information related to the crash is urged to call Trooper Janelle Smith at 603-223-8496.

Jordan Cuddemi can be reached at jcuddemi@vnews.com or 603-727-3248.