Updated: 2:32 p.m.

Officials are warning visitors to several beaches in the Seaside and Cannon Beach area to watch out for sharks, after dorsal fins were spotted offshore.

According to a press release sent out by the Oregon Parks and Recreation Department, "A person surfing off the north Oregon coast around Haystack Rock near Cannon Beach, and a visitor in Seaside both reported shark sightings Tuesday, July 18."

"We've got more than half a dozen signs up," Chris Havel, spokesperson for Oregon State Parks said over the phone Wednesday.

"It's generally the surfers that need to be aware of this," he added, saying people playing in shallow water don't need to be too worried about sharks.

Havel said it is unclear from the sighting what kind of shark was spotted. "There's 13 different species of shark that live off the north Oregon Coast," he said.

He confirmed that one of those species is Great White.

Be advised, there have been recent sightings of shark dorsal fins in the Cannon Beach area. State Parks will be posting warning signs on local beaches soon. Posted by Cannon Beach Police Department on Tuesday, July 18, 2017

The timing of the shark sighting lines up perfectly with the summer TV schedule: Shark Week on the Discovery Channel starts Sunday.

-- Lizzy Acker

503-221-8052

lacker@oregonian.com, @lizzzyacker