TERRE HAUTE, Ind. -- Investigators said late Wednesday that they found no sign that the freight truck driver who was involved in a crash that killed two officers on bikes applied brakes before the crash.

The freight truck hit a support van that slammed into the group of bikers, killing Indiana State Police Lt. Gary Dudley and former Lake County Police Chief Gary Martin on Tuesday in Vermillion County. The bikers were on a charity ride for Indiana Concerns of Police Survivors, a group that helps family members of officers killed in the line of duty.

Police said the truck's driver is cooperating with the investigation, which could span more than a week.

A report will be sent to the Vermillion County prosecutor, who will consider possible criminal charges.

Investigators want to talk to anyone who might have seen the riders after they stopped for lunch at a truck stop near State Road 63 and exit 4 on Interstate 74. Investigators were also working to determine whether the riders and their support van followed the proper steps to ensure their safety as they biked along the highway. Police asked anyone with information to call state police at 812-299-1151 or 812-299-1152.