A pedestrian was struck and killed on the Bay Bridge Tuesday morning, after they were reportedly spotted running between cars on the structure's lower deck.

Speaking with CBS 5, CHP officer Damian Cistaro says that the collision occurred early this morning near the Fourth Street off-ramp from the bridge.

The pedestrian, who they characterize as"wandering," was first reported at 3:17, KRON 4 reports, by a caller who said they saw someone "walking around on the lower deck of the Bay Bridge near 4th St." Another call reporting the collision came in soon after, they say.

According to CHP officer Jake Johnson, who spoke with NBC Bay Area, "authorities initially received a call about a person running in and out of lanes on the freeway."

The pedestrian "ended up on top of a grey Porsche and was pronounced dead at the scene," Johnson says.

As of publication time, the San Francisco Medical Examiner's Office had not publicly released any additional details on the deceased, including gender, age, or name.

Following the crash, the 1, 2 and 3 lanes of Eastbound 80 were closed for an investigation into the collision. By 4:38 a.m., they had reopened and traffic resumed in the area.

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