By Wilson Walker

MILL VALLEY (KPIX) — On Tuesday afternoon in Muir Woods National Monument, five trees toppled onto a trail, striking two people and killing one of them.

“These were visitors exactly where they are allowed to be,” said Charles Strickfaden, a spokesman for the National Park Service. “It just seems to be an unfortunate, tragic event.”

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It was nearing sunset on Christmas Eve, about a half-hour before the park was set to close. Three people were walking on Hillside Trail when five trees collapsed like dominos.

“I initially thought it was like an earthquake or something. I had no idea. I had never heard a sound like that,” hiker Alex Shepard told KPIX.

Shepard, visiting from New York, was hiking with his mother when the trees fell. “We were just finishing our hike when we heard this colossal noise — maybe 250, 300 feet away — and watched a huge redwood fall from the hillside down to the trail below,” he added.

A 29-year-old man was killed, according to Ben Ghisletta, a county fire captain.

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“One person escaped unharmed,” explained Strickfaden. “The woman was sent to the hospital and, unfortunately, one person was deceased. That trail has been closed because of the fallen trees. Access has been blocked until we can remove it.”

Muir Woods Fatality

A Muir Woods trail where a hiker was fatally struck by a falling tree. (CBS)

Most of of the park was open on Christmas Day. No one interviewed by KPIX had heard about what happened the day before.

“The trees may have been weakened due to the heavy rain that we’ve had in the last week or so,” Strickfaden said.

The Park Service is investigating what is a very rare kind of incident here, a place where nearly one million people per year visit to view the trees nearly a thousand years old.

“We consider this a totally isolated event and it’s a tragedy,” Strickfaden said. “Our prayers are with the family.”

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© Copyright 2019 CBS Broadcasting Inc. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. KPIX 5’s Andria Borba contributed to this report