(NewsNation) — The search for a missing woman in California is ongoing after she disappeared during an open water swim south of San Jose.

The 55-year-old, who remains unnamed, has not been seen since undertaking her weekly group swim Sunday.

According to NewsNation local affiliate KSBW, an eyewitness on the shore saw a “large splash” in the water. Police said all in the group returned to shore safely, the missing woman aside.

The city of Monterey said two witnesses indicated the woman may have encountered a shark while swimming offshore near Lovers Point, three miles south of Monterey.

Her family has been notified of her disappearance.

“She’s a 55-year-old blonde woman with blue eyes who is currently missing and who we’re searching for,” said Commander Brian Anderson with the Pacific Grove Police Department, via KSBW.

The U.S. Coast Guard, Monterey Fire Department, Seaside Fire and CAL FIRE have all been part of the search efforts.

In a press release, the city of Monterey announced Lovers Point Beach in Pacific Grove and McAbee and San Carlos Beaches in Monterey will remain closed through Tuesday.

A beach advisory will remain in place for Asilomar State Beach, Monterey Municipal Beach, Del Monte Beach and Monterey State Beach through Tuesday.