Big Island police have determined that a man involved in a one-vehicle crash on Ali'i Drive on March 25 died of a heart attack and not from injuries he suffered in the collision.

Wesley I. Hirata, 36, was driving a white 2007 Toyota pickup truck north on Ali'i Drive shortly before 8:58 a.m. when the truck ran off the road and struck a rock wall 100 feet south of the 3.5- mile marker.

Police ordered an autopsy that proved that Hirata, of Honoka'a, died of a heart attack.

Those findings prompted police to reduce the traffic fatality count for the Big Island for this year to 11 compared with 12 at this time last year.