One of those who died in Monday’s series of crashes on Interstate 55 has been positively identified, three have been “tentatively” IDed, and two others are still unknown to investigators.

The Illinois State Police Tuesday asked for the public’s help finding the identities of those two, who were among the six who died and dozens injured in crashes authorities say was caused by a dust storm on I-55 near Springfield.

One of the unidentified victims was driving a blue Chrysler 300 and the other person was driving a Hyundai.

Anyone who has an acquaintance who drives these types of vehicles and would been in the area south of Springfield on Monday morning, are asked to call 618-346-3653.

No other information about the vehicles was released by Illinois State Police Director Brendan Kelly during a news conference Tuesday morning in Divernon.

Kelly said only that the two were adults.

“We want to make sure their family, the people that are out there, their loved ones that are concerned about their whereabouts that we’re able to provide some closure and proper identification of who these two victims are,” Kelly said.

Kelly said investigators have positively identified one victim and tentatively identified three others.

Illinois State Police Troop 8 reported that 88-year-old Shirley Harper of Franklin, Wisconsin, was one of those who died.

The crashes occurred on Interstate 55 near Milepost 76 north of Farmersville in Montgomery County.

Due to the severity of crashes, state police called out crime scene investigators to assist troopers, Kelly said, but he noted there was not a criminal investigation.

There were 37 persons injured with victims ranging in age from 2 to 80.

Kelly also said there were at least 72 vehicles involved but that number could be higher if some motorists had damage to their vehicle but were able to drive the vehicle from the scene.

The dust storm occurred when there were high winds Monday morning after farmers in the region had been plowing their fields and there had not been rain in recent weeks.

Kelly said the deaths were a result of a “terrible series of converging circumstances, very unusual.”

“We are all grieving for the people who died here yesterday.”

The highway was reopened Tuesday morning.