The man who is suspected in the crazed and brutal attack on a 94-year-old woman in Chinatown on Saturday has been arrested, police said Tuesday.

James Bartley, 52, of San Francisco, was charged Tuesday with four felonies, including aggravated assault, battery causing serious injury, elder abuse and criminal threats, police Sgt. Michael Andraychak said.

The incident occurred at 4:45 p.m. at Stockton and Sacramento streets, police said. The victim was crossing the street when a man approached her from behind and punched her several times in the head “for no apparent reason,” according to police.

The victim subsequently fell and possibly fractured her skull. She is “still hospitalized in life-threatening condition, but is showing signs of improvement,” Andraychak said.

The incident was one of many in a particularly bloody few days in San Francisco. Besides the assault, there were three homicides, two suspicious deaths and a suicide involving chemicals that led to an apartment building being evacuated.

Cops have been “pretty busy” since Friday morning, police spokesman Officer Albie Esparza said Monday.