FORT KNOX, Ky. (AP) _ A large truck carrying Marines from a training exercise overturned on a rain-slick road, killing three and injuring nine, officials said Sunday.

Lt. Col. Don Harlin, a division commander at Camp Lejeune, N.C., said 12 Marines were returning from a gunnery range Saturday night at Fort Knox when the driver apparently lost control as the truck began descending a steep road.

''(That truck) crests at a fairly slow speed,'' Harlin said. ''The road conditions were exacerbated with mud and a film on the road from heavy use ... and that may have contributed to the accident.''

Lt. Col. J.C. Allard, a Fort Knox spokesman, said the names of the victims were withheld pending notification of relatives

Seven Marines were thrown from the canvas-roofed bed of the truck as it spun several times and overturned, apparently after slamming into an embankment, Harlin said.