UPDATE 2 p.m., Apr. 18: Lifeguards removed the shark advisory signs at Silver Strand.
SAN DIEGO (KGTV) -- Lifeguards warned beachgoers in Silver Strand after several agencies spotted a shark they say could be a great white off the coast Wednesday.
According to authorities, the shark was initially spotted by Border Patrol agents in a helicopter above Imperial Beach around 10:30 a.m.
The shark was also spotted by a lifeguard in a boat approximately two miles off the coast of Imperial Beach.
The shark is believed to be between seven and eight foot long. Lifeguards in Imperial Beach say they believe the shark could be a great white.
The shark was again seen about half a mile off the coast of Silver Strand, prompting lifeguards to warn beachgoers.
Lifeguards chose not to issue a formal public warning because the shark was of moderate size, wasn't behaving aggressively and was in an area with few people nearby, City News Service reports.
The sighting comes less than a year after a 13-year-old boy was attacked by a shark while lobster diving off the coast of Encinitas in September of 2018.
Researchers later confirmed that the shark that attacked Keane Hayes was a great white.