A Colorado woman and her sister-in-law have apparently drowned during a trip to Kauai.

Police say 33-year-old Heather Westphal of Washington, D.C., and 38-year-old Tonya Cataldo of Parker (Colorado) were strolling along Queen's Bath in Princeville yesterday when a large wave knocked Westphal off her feet and onto the rocks.

Cataldo tried to help her up, but a second large wave swept both women into the water. Westphal's husband swam to rescue them, but the current was too difficult and he returned to shore.

Lifeguards and firefighters were unable to resuscitate the women.

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