WARREN COUNTY • An O’Fallon, Mo., man who clung to a semi for several miles on Interstate 70 later jumped off and was fatally struck by another semi truck while running in and out of traffic Tuesday.

Darryl D. “Manny” Boyle Jr., 20, was struck in a westbound lane of the interstate east of Jonesburg, Missouri Highway Patrol Sgt. Al Nothum said. He was pronounced dead shortly before 6:30 p.m. at a hospital.

Boyle’s older sister said he probably became paranoid while at a construction-training site in High Hill, Mo., and had gotten on the semi in an attempt to get home.

Perhaps he was exposed to marijuana, the sister, Jasmine Boyle, 25, of St. Louis, said. Her brother had been diagnosed with paranoia and drug-induced psychosis, “so if he was ever around marijuana it made him paranoid,” she said. ”A doctor said being around it, the aroma in the air, would make him paranoid.”

“He was just paranoid, he was sick at the moment,” Boyle said as she tried to make sense of her brother’s death. “He became paranoid and he was trying to get home, maybe he lost where he was going.”