SCHROEPPEL, N.Y. (AP) — Authorities are still trying to figure out why a man apparently deliberately drove the wrong way on a central New York highway before crashing into two other vehicles, killing himself and twin sisters on a Christmas shopping trip.

State police say 68-year-old Bruce Drury of Syracuse drove the wrong way for seven miles on state Route 481's southbound lanes on Monday morning, at one point serving around a trooper who had parked his cruiser in Drury's path in an effort to stop him.

Soon after Drury's car slammed into two other vehicles in Schroeppel, north of Syracuse. Drury and two passengers in the first vehicle struck, 69-year-old sisters Louise Porter and Linda Robillard, were killed. Porter's husband was injured.

Troopers say it didn't appear Drury had suffered a medical emergency. Toxicology test results are pending.

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