SAN JOSE (CBS SF) — A train trestle that crosses Willow Creek in San Jose has been damaged and placed out of service after it caught on fire early Wednesday morning, according to the San Jose Fire Department.

The call for the fire came in at 3:15 a.m. and the structure was engulfed in flames when firefighters arrived, San Jose Fire Capt. Daniel Vega said.

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Vega said fire crews believe the fire started in a homeless encampment underneath the trestle, but investigators do not know if it was set intentionally or not.

He said it does not appear any accelerants were used in the blaze, which was brought under control at 4:42 a.m.

Nobody was injured in the fire and there are no suspects in custody Wednesday afternoon, Vega said.

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Caltrain, Union Pacific and Amtrak trains operate on the tracks and will run on a single-track basis on a concrete train trestle that also crosses the creek while the wooden trestle is out of service.

Trains passing through the area had already been single-tracking through the area since June for the Los Gatos Creek Bridge Replacement Project, which Caltrain spokesman Dan Lieberman said should finish next week.

“We had been single-tracking after the Willow Street bridge heading north, but doing it before it shouldn’t result in further service disruption,” Lieberman said.

He said it would take some time to evaluate the damage to the bridge.

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