Deputies say the man suffered bite wounds all over his body - including a severe bite wound to the neck - and is lucky to have survived the attack.
The drama began as the man was out walking in the 10200 block of 18th Ave SW at about 12:15 a.m., said Sgt. Patrick McCurdy of the King County Sheriff's Office.
Three dogs suddenly rushed up to the man, knocked him down and began ripping at his flesh with their teeth. The man pulled out his pocket knife and fought back, inflicting injuries on one or more of the dogs.
Some passers-by witnessed the attack and called 911 as a neighbor tried to pull the dogs off. Another person driving by tried to run over the dogs with his car.
Deputies arrived on the scene shortly afterward and seized the dogs after they ran off. The canines were located by following bloody paw prints and with the aid of a sheriff's helicopter equipped with heat sensors.
"One of his neighbors tried to pull the dogs off, even though they were in the middle of the attack, a kind of frenzied attack," said King County sheriff's deputy Patrick McCurdy.
Medics treated the victim and took him to Harborview Medical Center for treatment of significant bite wounds all over his body, McCurdy said.
A preliminary investigation found that two of the dogs had been locked in a yard in the 10400 block of 18th Ave SW but somehow got loose. Two other people reported being cornered by the dogs earlier.
Michael Veidt owns two of the dogs, a 7-year-old bull mastiff named "Savage" and a 6-month-old American terrier named "MV." Veidt is cooperating with deputies and will likely not face charges because the dogs escaped from a locked yard.
He said the dogs are "family oriented" and "loving," but he believes fireworks got them riled up.
"Savage, we've had him since he was a baby, and all our dogs are family-oriented dogs," Veidt said.
The third dog appears to be a pit bull, but the owner of the other two dogs did not recognize it.
The dogs will be evaluated and checked for rabies before authorities decide whether to return them to their owner.