DEL MAR -- A trio of robbers bound a housekeeper and resident at a multimillion-dollar Del Mar home Tuesday before breaking into the home's safes, a Sheriff's Department sergeant said.

Based on statements from the two victims, Sgt. Bill Dreyer said three men with blue bandanas over their faces entered the residence about 11 a.m. in the 2100 block of David Way, which overlooks Jimmy Durante Boulevard. They probably came in through an open or unlocked door, Dreyer said.

They encountered a housekeeper, a woman in her 30s, vacuuming and hit her over the head with a tool, Dreyer said. One of the robbers pointed a silver revolver at her while the others bound her with duct tape and moved her into the master bedroom, they said.

The group then found the homeowners' 27-year-old son in one of the bedrooms working on a computer, Dreyer said. They bound him and demanded that he show them the safes.

The man showed the robbers three safes, but didn't know the combinations, Dreyer said. The thieves pried the safes open and took money and jewelry, he said. Before they left, the suspects bound the two victims tightly with more tape.

The man eventually freed himself and called 911, Dreyer said. Detectives recovered tools and duct tape from the scene that will possibly examined at a crime lab, he said.

The housekeeper, who was deeply upset, went to a hospital with moderate head injuries, Dreyer said.

The value of the loss was not known Tuesday. The suspects were described only as two white men and one Hispanic man in their 20s.