A 36-year-old crew member of a charter boat was injured Tuesday when she was attacked by a 130-pound bull mastiff at the Kaneohe Bay sandbar, authorities said.

The attack took place at about 2:30 p.m. on the north end of Ahu o Laka where commercial boats are allowed to dock, said Deborah Ward, spokeswoman for the state Department of Land and Natural Resources.

A supervisor with the Emergency Medical Services Division said the woman was taken to the hospital in serious but stable condition.

Rob Mathews, operations manager of Dreamer Yacht Charters, said the woman was a crew member setting anchor for the vessel Dreamer when the attack happened before two guests on a luxury tour.

"It’s quite horrifying," he said.

While the woman was in the water, two dogs ran down the sandbar toward her, and one dog attacked her "completely unprovoked," he said.

"The larger one jumped up on her and started to maul her and actually took her off her feet and put her underwater," he said. The woman sustained cuts behind her ear, at the back of her neck and on top of her head, he said. She remained at the hospital Tuesday evening getting stitches.

He said another boat from the company took the woman back to Heeia Kea Boat Harbor where the crew was met by the Fire Department.

Ward said the dog was released to its owner, who could face charges under the city’s dangerous-dog law.