WARREN TOWNSHIP (AP) - A driver was going more than 100 mph when he crashed into another vehicle on an interstate in northern New Jersey over the weekend and struck some trees, killing himself and his son, state police said Monday.

Two people in the car the man hit were then struck and injured by another driver a short time later.

Authorities say a state trooper started pursuing Stephen Weekes at around 8:45 p.m. Saturday after the 34-year-old from Bethlehem, Pennsylvania, sped by him in a westbound lane of Interstate 78 in Somerset County.

The trooper activated his emergency lights and started pursuing the speeding car but was still a far distance away when Weekes' vehicle hit another car and left the highway, striking some trees.

Weekes and his 9-year-old son, Anthony Weekes, of Jamaica, New York, were pronounced dead at the scene.

Meanwhile, the driver of the car that Weekes hit and his passenger got out of the vehicle, which ended up in the left shoulder and left lane of the highway. Both men were then struck by another driver who lost control of her vehicle as she approached the accident scene, police said.

The two men - George Frisoli, 22, of Basking Ridge, and Calvin Spann, 23, of Maywood - and the woman, 32-year-old Eliza Deck of Clinton, were all taken to hospitals. Details on their conditions were not disclosed Monday.

It's not clear why Weekes was traveling so fast. Authorities say there was evidence in the car indicating possible intoxication, but they noted that the medical examiner's lab tests will not be complete for several weeks.

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