S.F. hit by 3 morning home invasions

Three people were injured in three daytime home invasion robberies in San Francisco over the weekend, police said, an unusual outburst of a crime that made up less than 1 percent of all robberies and burglaries in the city last year.

The first robbery occurred on the 100 block of Farallones Street in the Ocean View neighborhood at about 8:15 a.m. Friday. Police said a suspect, described as a 30-year-old woman, rang the doorbell and used a knife to force the 26-year-old female resident around her home while she took jewelry, cell phones and money.

The intruder forced the woman into a chair, placed a towel over her head, tied her up with extension cords and ransacked the rest of the home, police said. The victim suffered a wound to the forehead but declined medical treatment.

The second home invasion happened on Amethyst Way in Diamond Heights at about 7:30 a.m. Saturday. The victim, an 85-year-old man, answered a doorbell to find no one there, police said. But when he went back upstairs, he found a man in the home he shared with a 79-year-old woman.

Police said the assailant physically forced the two residents to walk around the house identifying items of value and made off with money, a tablet, a smartphone, a computer and jewelry before fleeing in a waiting car. Another suspect drove off with a vehicle belonging to the victim, who complained of pain sustained during the attack.

The third home invasion took place Sunday on the 300 block of Buchanan Street in the Lower Haight. A 55-year-old woman was awakened at 5:30 a.m. by a man punching her in the stomach and head, police said.

Another man taped her mouth shut, and the two suspects ransacked her apartment, stealing money she had in her closet, police said. The victim was treated for injuries at the scene.

No arrests have been made in the attacks. Officer Grace Gatpandan, a police spokeswoman, said the cases appeared to be unrelated and would be investigated separately.

Last year, 69 home invasion robberies were reported in San Francisco, a decrease from the 78 reported in 2013, according to police data.

Vivian Ho is a San Francisco Chronicle staff writer. E-mail: vho@sfchronicle.com Twitter: @VivianHo