Harshita Nair, 21, and Mahial Sran, 20, both of Fremont, died last Wednesday after being swept into the ocean near Panther Beach's notorious "keyhole" — a natural archway that closes without warning when the tide rises, leaving no way out except the water.

Their deaths — the latest in a string of emergencies along a single mile of Santa Cruz County coastline — have renewed calls from public safety officials for beachgoers to understand how quickly the terrain around Panther Beach can turn lethal. Emergency personnel have carried out five rescues in the one-mile stretch between Panther Beach and Bonny Doon Beach in the past month alone.

SANTA CRUZ COUNTY — They were near the keyhole when the water came.

Harshita Nair, 21, and Mahial Sran, 20, both residents of Fremont, were at the south end of Panther Beach last Wednesday afternoon — close to a natural cleft in the sea cliffs that separates Panther Beach from Yellow Bank Beach — when rising tides swept them into the ocean. Both women were pulled from the water by rescue crews. Neither survived.

The emergency unfolded quickly. A 911 call came in at 5:08 p.m. Wednesday reporting a person in the water near Panther Beach, according to Santa Cruz County Fire Capt. Kyle Breton. By the time responders were en route, updated information indicated two people might be in the water.

Rescue swimmers from Santa Cruz City Fire and California State Parks deployed into the surf. One woman was pulled onto Panther Beach. The other had been carried to Yellow Bank Beach — an area so difficult to access by land that a helicopter had to hoist both the patient and rescue personnel up to the bluffs above it. Both women were taken to the hospital in separate ground ambulances. One died that night; NBC Bay Area confirmed Saturday that both women had died.

The geography of the location is key to understanding how the accident happened. The keyhole — a gap in the coastal cliffs at Panther Beach's southern end — is a passage that thousands of visitors use each year to walk between the two beaches. At low tide it's accessible; at high tide, the ocean fills it completely, cutting off anyone on the Yellow Bank Beach side. The only way back is through the water.

"A lot of people go through when the tide is lower, not realizing that you cannot get back out of Yellow Bank Beach once the tide comes in," Breton told the Santa Cruz Sentinel on Friday, two days after the incident.

There were conflicting initial accounts of exactly where the women were when the water struck — some reports indicated they were sleeping near the keyhole; others suggested they were awake and near or just through it, Breton said. Whatever the sequence, the result was the same: water came in, likely a combination of high tide and a sneaker wave, and caught them before they could react.

Panther Beach has been drawing increasing emergency attention this season. Beyond Wednesday's fatalities, fire crews have logged five rescues in the one-mile stretch between Panther Beach and Bonny Doon Beach over the past month, Breton said. The area sits within a broader zone of elevated coastal hazards: the National Weather Service has issued beach hazards statements this weekend warning of long-period southerly swell, elevated sneaker-wave risk, and strong currents from San Mateo County south through Monterey. The Dissent reported Sunday on a NWS flood advisory in effect for the Bay Area through Thursday, with tides running 1.9 feet above normal — conditions that push water further into cliff features like the Panther Beach keyhole than casual visitors expect.

The multi-agency response to Wednesday's emergency included Cal Fire, Santa Cruz County Fire, Santa Cruz City Fire, the Santa Cruz County Sheriff's Office, and California State Parks. Breton urged visitors to check tide conditions before entering the beach and to understand the hazards specific to the area.

The Santa Cruz County Sheriff's Office had not released further information on the identities of the women as of Friday. NBC Bay Area confirmed both names and their Fremont residency Saturday.

Nair and Sran are the latest Bay Area residents killed on a stretch of Central Coast beach that, for all its beauty, offers no room for error when the tide turns.