Metairie — Causeway Police searched Lake Pontchartrain on Wednesday night for at least one person and a truck that might have fallen into the water after the vehicle caught fire and exploded.

Carlton Dufrechou, Lake Pontchartrain Causeway’s general manager, said a driver headed northbound called bridge police about 5:10 p.m. to report a burning truck on the southbound bridge, about 4 miles from the south shore. The driver then told police the truck exploded, Dufrechou said.

Damage to the bridge’s rail led police to believe the truck and its occupant or occupants went into the water, Dufrechou said. Lights were being brought in to assist in the search, he said since it was too dark to immediately know for certain if there was anyone or anything in the lake.

It was not immediately clear if other vehicles were involved, Dufrechou said.

Police shut down the northbound and southbound bridges minutes after they received the call of the fire and explosion. They reopened the northbound span about 6 p.m.