A young man went on a violent spree in an Anchorage complex for seniors. An 88-year-old fought him off.

Stanley Sienda, 88, had just returned from his customary daily jog one afternoon in late April when he heard someone pounding on the door of his apartment in Chugach View, a Fairview public housing complex for seniors.

“I open the door,” said Sienda. “And somebody grabbed me and bit me on the neck.”

He found himself grappling on the floor with a stranger, a far younger man who was biting and kicking him with heavy shoes.

“I knew this person was real dangerous,” Sienda said this week, a wiry elder in an Alaskan Brewing Co. sweatshirt and sweatpants. “I could feel his teeth on my eyebrow, my head, everything.”

After what seemed to Sienda like a long while, he was able to break free from the assailant and scramble into the hallway.

By the time police arrested Justin Koonuk, 24, he’d assaulted four different people in the senior apartments. Sienda was the last one.

Koonuk is now charged with assault in the case. He also has an open assault charge from March, stemming from an incident where a police officer saw him punch a man in the face on a sidewalk in Midtown.

The charging document in the April assaults says Koonuk went to the Chugach View apartments to drink in the room of a resident. At some point, this went badly and Koonuk allegedly grabbed a cane from his host and assaulted her with it, along with another man in the apartment. They were able to push him into the hallway, but Koonuk continued his tear through the building, striking another man who opened his door before going upstairs and banging on Sienda’s door.

Sienda was the worst injured: He has broken ribs and deep bruises, and weeks later lacerations remain on his head and neck. Because the bites broke skin, he will need to undergo testing for blood-transmitted disease. Photos taken of his apartment after the attack show streaks of blood and even a cooking pan bent in the struggle.

Born in Connecticut, Sienda rambled around the country working on boats in Louisiana and as a machinist before driving a van to Alaska more than 20 years ago to settle. As he entered his 80s, he still took yearly summer trips to backpack around Europe via a Eurorail pass. He says he runs every day on the Chester Creek trail, sometimes all the way to Lake Otis. But a stranger bursting violently into his own apartment?

“I’m not a scaredy guy,” he said. “But I knew he was trying to kill me.”

The rampage has left the elderly residents of one of Anchorage’s largest public housing facilities on edge. Another resident started a petition to management raising concerns about safety, and 50 or 60 people have signed so far, residents say.

Mary Wolcoff is a receptionist at the Anchorage Senior Center, a separate day center where many Chugach View and Chugach Manor residents spend time. She describes herself as a longtime friend and advocate for Sienda.

Wolcoff says security isn’t good enough at Chugach View. While residents have keycard access and doors are locked automatically, there are just too many entrances, and ample opportunities for people to slip in unnoticed behind residents.

“There’s like four or five young men who come in there and smoke marijuana in the laundry room,” Wolcoff said. “They dare the residents to confront them. And you know, the residents are too afraid to confront them.” (Building management says they reviewed video from hundreds of cameras and have not found evidence of people sneaking in to smoke in the laundry room.)

Sienda said someone tore a phone off the wall, and ripped away a coin machine. In the mornings, he has found groups of people sleeping at the entryway of the building. The problems seem to have built over the last two years, when Sullivan Arena became a mass-care shelter.

The apartments are owned and operated by Alaska Housing Finance Corp., a quasi-governmental agency that uses federal HUD funding.

Cathy Stone, the director of public housing for the Alaska Housing Finance Corp., says Chugach View is secure. The man who assaulted four seniors was invited into the building, she said — he didn’t sneak in.

“We don’t really mandate what guests (residents) can or cannot have. That’s their choice,” she said. “We don’t control that. But we do caution people that it could jeopardize their housing.”

Low-income seniors pay 28% of their income for a one-bedroom apartment at Chugach View or Chugach Manor. The waitlist is formidable: Some 827 people are waiting for a spot.

The apartments have full-time property managers, maintenance staff and a person whose sole job is to deal with resident concerns, she said.

“Safety and security is critical to us, for all our residents,” she said. “And yeah, we take it seriously. We respond quickly and address those concerns. And this will be managed.”

Back in 2007, residents and police raised concerns about drug dealing, theft, harassments, weapons and even sexual assault within the apartments, according to Daily News reporting from the time.

“I don’t usually go out of my apartment unless we have bingo,” one resident told the newspaper.

At the time, it was attributed to a drop in the number of seniors being allowed to live in the apartments. Today, the average age is 68.

Wolcott, the receptionist who is a friend of Sienda’s, said the increase in criminal activity around the public housing is worrisome for the vulnerable people who live there. She sees groups of much younger men who hang out in the areas as the culprits.

“I wish they would look at their grandparents and say, ‘I wouldn’t want to do this to my grandparent,’” she said.

Koonuk could not be reached for this story. Court records show his bail was set at $2,500 but he remains at the Anchorage jail. Sienda says he’ll be at every court appearance.