A 29-year-old man has been arrested for allegedly assaulting a woman in her 70s in downtown Palo Alto last week, according to police.

The incident occurred at about 4:53 p.m. on June 15 in the alley that runs between the 300 block of University Avenue, police Lt. Con Maloney said on Monday.

The woman and the man, who were acquaintances, got into an argument that escalated. The man allegedly punched the woman in the head, knocking her to the ground. The woman suffered moderate injuries to her head and arm and was transported to a hospital, Maloney said.

The man was identified as Zachary Lee Estrada, whom police described as without a permanent address. Police booked him into Santa Clara County jail on suspicion of battery causing serious bodily injury and for committing a crime causing great harm against an elderly person, which are both felonies. He appeared in court for his initial arraignment on Friday, June 17, and is scheduled to enter a plea on Aug. 1.