Tony Reed
Del Norte Triplicate

It is not yet known what caused a loud boom, heard and felt by many Crescent City residents late Sunday night.

The resounding boom shook walls near Crescent City Marina and echoed slowly away at about 9:13 p.m. The boom, which was much louder than a gunshot, was not followed by any other sounds and did not generate a response from local fire departments.

Undersheriff Bill Steven said several calls came to 911 with most placing the boom somewhere near Crescent City Harbor. Others said it could be heard in the area of 9th and 10th streets, “from J Street to U.S. 101.”

Police Chief Ivan Minsal said he was off duty in his home in north Crescent City at the time and did not hear the boom.

Steven said officers responded to the reported areas and searched but found no signs that anything might have recently exploded.

“It remains a mystery,” he said.

On social media, speculation ensued as to whether the noise was a sonic boom or other type of explosion.

Staff at Beale Air Force Base near Marysville said they had no planes in the area Sunday. Public Information officers at Kingsley Field in Klamath Falls, Oregon, which sometimes has F15 fighter pilots training over Del Norte County, could not be reached.