WORTH, Ill. (CBS) — A south suburban man died over the weekend after crashing his car on the Tri-State Tollway, stripping naked, and walking into traffic.

In so doing, the man also indirectly caused another accident, police say.

Witnesses said Daniel Thompson, 35, of Robbins, had been driving a black 2005 GMC pickup truck at a high speed in the northbound lanes of the Tri-State (I-294) shortly before 6 p.m. Sunday. He rear-ended another car and ended up slamming into the right guardrail just south of 95th Street, Illinois State Police said.

Afterward, a mundane traffic accident quickly turned profoundly bizarre.

Thompson took off all his clothes, got out of his pickup truck, and walked into traffic buck naked, state police said.

As he stood there on full display for all the drivers on the tollway, Thompson, of Robbins, was struck and killed by a white rental 2010 Chrysler Town & Country minivan in the far left lane. He was dead at the scene, state police said.

The driver of another car, a black Chevrolet Cobalt, swerved to avoid the accident that killed Thompson, but ended up getting into a separate accident. The car struck the right guard rail, and three people were hospitalized with non-life-threatening injuries.

State Police couldn’t say what made Thompson strip naked and walk into traffic, and are investigating whether drugs or alcohol were involved, Master Sergeant David Schneider said Monday.

The minivan driver who hit Thompson will not be cited, state police said.

The Sun-Times Media Wire contributed to this report.

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