Two women died after they were “caught off guard” and swept to sea during their visit to a Northern California beach, officials said Tuesday.

They were swept away about 5 p.m. Wednesday near Yellow Bank Beach just north of Santa Cruz, fire officials said.

Eight rescue swimmers were dispatched and found the women and returned them to shore, officials said. The women were taken to Dominican Hospital, where they died, officials said.

“It is unclear what they were doing when they were swept into the ocean,” Cal Fire spokesperson Michael Horn said in a statement. “What we do know is they were caught off guard.”

Harshita Nair, 21, and Mahial Sran, 20, both from the nearby San Francisco Bay Area city of Fremont, died after they were “unexpectedly washed out” to sea, according to Santa Cruz County sheriff’s spokesperson Ashley Keehn.

Horn said the deaths should be a reminder to beachgoers to avoid turning their backs to the ocean and a warning that if “the sand is wet, waves have been there recently and will return at any time.”

“Always check a local tide chart before visiting beaches,” he said. “If the tide is rising, do not put yourself in a position where your only exit path can be cut off by water.”