A great white shark was spotted off the coast of Imperial Beach on Tuesday, according to city officials.

Lifeguards said the shark was spotted near Imperial Beach Boulevard at 9 a.m. A local took a picture of the sighting, and presented it to lifeguards.

The picture was then sent to a shark research facility, which confirmed the dorsal fin belonged to a great white. Researchers believe the shark photographed was between 16 and 18 feet.

The shark reportedly stayed in the area for a moment, then swam on.

"We haven't seen anything like this since the 1950's," said Lifeguard Capt. Robert Stabenow.

The beach is open, but signs warning people of the shark sighting have been placed throughout the beach.

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