Tourists walk along the water at Popham Beach State Park in Phippsburg in this file photo. Credit: Brian Swartz / BDN

A great white shark sighting closed a popular beach on the midcoast.

Popham Beach in Phippsburg is Maine’s busiest state park beach, but it closed Wednesday afternoon after a great white shark sighting.

The shark was reported around 5:20 p.m. The state closed the beach less than an hour later.

The beach closing happened on the second anniversary of a fatal shark attack in nearby Harpswell.

Since that attack, purple flags are now used to make swimmers more aware of sharks.

Officials urged people not to swim near seals or groups of fish and stay in a group if you can when you’re in the water.

Popham Beach was scheduled to reopen at 9 a.m. Thursday.

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