WAKEFIELD,N.H. (CBS/AP) – Police say an unlicensed driver trying to pass a car on a snowy road in New Hampshire died after colliding head-on with a car carrying four Secret Service agents on Democratic presidential candidate Hillary Clinton’s protective detail.

Wakefield police say the agents were in a Ford Taurus on Route 16 when they were hit head-on by a Mercury Sable that crossed the double yellow line just after 7 p.m.

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The driver of the Sable, 45-year-old Bruce Danforth, died at the scene. Wakefield Police Chief Kenneth Fifield says Danforth didn’t have a valid license.

Bruce Danforth. (Photo credit: Wakefield, NH Police)

Bruce Danforth. (Photo credit: Wakefield, NH Police)

The four Secret Service agents, who were all on duty, were taken to Frisbee Memorial Hospital where they were treated for injuries. According to the agency, the injuries are serious, but not life-threatening. The agents names have not been made public.

“Please join us as we keep all the victims of this accident and their families in our thoughts and prayers,” Secret Service Director Joseph Clancy said in a statement Wednesday.

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Clinton was at a campaign event at Berlin High School Tuesday evening.  The school is about 80 miles away from Wakefield.

Clinton says she was saddened to hear of the crash.

Two passengers in the Sable, 21-year-old Kristina Buswell and 35-year-old Natasha Meroski, were also taken to the hospital. Their conditions are not known.

Anyone with information about the crash should call Wakefield police at 603-223-8607.

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