A shirtless maniac armed with a fistful of long-handled kitchen knives savagely stabbed an elderly dog-walker and a restaurant worker Saturday during a random Manhattan rampage that ended when an off-duty police officer shot the attacker from point-blank range.

The crazed assailant repeatedly stabbed the 67-year-old woman as she walked her black Scottish terrier through the typically quiet East Side neighborhood, plunging the knives into her arms, face, neck, and abdomen, a deputy police chief, Michael Collins, said.

Witnesses described the attacker, a lanky 38-year-old man, repeatedly raising his hands above his head as though swinging a club at the helpless victim, her dog still tethered to her wrist by a leash. The woman, a neighborhood resident, was rushed into surgery at Bellevue Hospital.

“It was crazy,” a nearby resident, Isi Harrison, 23, said. “I was right next to her. And then they shot the guy.”

The bizarre episode left behind a trail of blood and stunned bystanders, including parishioners at an Armenian cathedral across Second Avenue. The elderly woman’s cane was lying in the intersection at East 35th Street, along with a pile of bloody towels and rubber gloves abandoned by EMTs and local store owners who rushed to her aid.

The stabbing spree started around 10:35 a.m. after the suspect argued with someone inside a nearby Second Avenue store. The irate man bolted the shop and headed north, walking into a barbecue joint and demanding to use the bathroom, Mr. Collins said.

Before anyone could respond, the man was inside the kitchen grabbing at knives and slashing one worker, Mr. Collins said. The wounded employee, his shirt covered in blood, staggered down Second Avenue with a gash to his face as the knife-wielding man approached a crowd standing outside the adjoining Gemini Diner.

The man, without a shirt and “acting like a maniac,” attacked the elderly woman for no apparent reason as bystanders and passing drivers gaped in horror, Mr. Collins said. The attacker knocked the woman down with a running tackle, a witness, Patrick Rizzo, said.

“He swung a knife right into the back of her neck, not stabbing but chopping like a sword,” Mr. Rizzo said. Another witness said the man, his demeanor “intense,” never said a word before targeting the woman.

Inside the diner, an off-duty police officer saw the mayhem and came outside to confront the suspect. The six-year veteran identified himself, and fired a single shot when the suspect responded by rising up and waving the knives, Mr. Collins said.

Even with the gunshot wound to his torso, it took five police officers to subdue the suspect, witnesses said. Police recovered four knives from the scene, Mr. Collins said.

The suspect and the wounded restaurant worker were also taken to Bellevue, where officials had no word on their conditions.