Police spokesperson Renee Witt said the man tackled a 16-year-old girl and a 19-year-old man, then walked away. When police arrived on the scene, the man ran and jumped into the lake at approximately 3:20 p.m., Witt said.
"This guy got down on the dock kind of nonchalantly, then he jumped into the water, started taking off all his clothes and starting swimming," said witness Susan Gillispie. "He just kept swimming across all the way, and he was hanging on a buoy."
The man swam to the middle of the water and was seen clinging to a buoy, naked.
Police officers on boats tried to get the man to swim to shore, but the man resisted, swimming away from the boats when they got too close. Police threw a life jacket at the man and he ditched the buoy and swam to Duck Island where he jumped out of the water and ran off.
He was seen back in the water a few minutes later, using a life ring police threw in the water for him and continuing to evade them. A police diver tried several times to wrangle the man, but he managed to slip away each time.
Police spent much of the time in the water trying to convince the man to surrender.
"The officer said the whole time he wasn't making much sense and was very incoherent the entire time," said Kyle Moore of the Seattle Fire Department.
The unidentified man remained on the loose for more than two hours, and was finally taken into custody at 5:48 p.m.
The two tackled victims, Daniel Gonzales and his sister, were taken to an area hospital. Gonzales suffered a badly cut lip and a broken finger in the scuffle, and his sister, Susan, suffered cuts to her arms and legs.
Daniel said the attacker came out of nowhere.
"I was walking with my autistic sister and apparently I got jumped. I didn't see it coming," he said.
Police say the 32-year old is facing a host of charges, including felony assault on two officers and two counts of misdemeanor assault on the brother and sister. He will likely also be charged with eluding police.
He's currently undergoing a mental evaluation.