The body of a woman reported missing from Yuma, Ariz., was found Tuesday in the back of a semitrailer delivering lettuce to a Hy-Vee grocery store distribution center in Iowa.

Sheila Kay Ross, 47, of McLoud, Okla., was reported missing Saturday by her husband, said Officer Clint Norred, a spokesman for the Yuma Police Department.

He said the Rosses arrived in their semi to pick up a load from a Dole plant in Yuma about 9:30 p.m. Saturday. Sheila Ross got out of the truck to get some paperwork but never returned, Norred said.

"After a while, Mr. Ross called us and the Yuma police searched the area and couldn't locate Mrs. Ross," Norred said.

Chris Friesleben, a Hy-Vee spokeswoman, said a dock worker found the body while unloading lettuce at the distribution center in Chariton, southeast of Des Moines.

Norred said the Rosses owned their own truck. Sheila Ross' body was found in the back of a truck owned by R&J trucking, of Youngstown, Ohio, he said.

"There is no sign of foul play and the incident appears to be a tragic accident," he said.

Norred said police do not know how Ross ended up in the truck, nor was there any immediate indication of how she died.

Officials with the Lucas County, Iowa, sheriff's office said the Iowa Division of Criminal Investigation was assisting in the investigation and that an autopsy would be performed.

Marty Ordman, a spokesman for the California-based Dole Food Co., said the company was notified of the incident and was waiting for more information from authorities in Yuma and Iowa.

A telephone message left Tuesday for officials at R&J trucking was not immediately returned.

Friesleben said the lettuce in the truck was destroyed.