The attacks Saturday morning - the first fatal one in the state in almost a century - was uncharacteristic of cougars, which are normally solitary animals that run off when confronted by humans, said Capt. Alan Myers of the Washington Department of Fish and Wildlife.
"He jumped the first victim and attacked him", said Sgt. Ryan Abbott, of the King County Sheriff's Office. "What we've learned is with wolves, cougars, and coyotes is actually killing them has the opposite effect, it throws them in what scientists refer to as social chaos". The cougar then dropped its first victim and chased after the running hiker.
Last October, the Seattle Bike Blog revealed how he had set up a Seattle chapter of Friends On Bikes to encourage black women and other marginalised people to get cycling. According to The Washington Post, the two realized they were being followed by the cougar and made loud noises to initially chase it away.
The two men were biking on a remote trail 30 miles east of Seattle when the cougar pounced. He was hospitalized with deep cuts and tears around his head and throughout his body.
The cougar had been standing over the body of the victim when authorities arrived, KIRO reported.
"The animal was found very close, across a gully from where the victim was placed by the cougar", said Captain Alan Myers, Washington Department of Fish and Wildlife.
This has led officials to believe something was wrong with the animal, and a brain necropsy is being performed to determine what that might be.
"This is not a normal way that a cougar acts", Abbott said. "And that bad experience means even though someone might bike to get around, a bad bike shop experience might dissuade them from learning more".
Wildlife officials say this is only the second fatal cougar attack in Washington State in 100 years.
Wildlife agents say the male cougar was about 100 pounds and three or four years old.
It's now unclear just why the mountain lion returned to attack the two Washington cyclists. As wildlife officials approached them, the cougar ran from the scene, a King County Sheriff's Office spokesperson tells CBS News. Rescuers flew him to a hospital, where he was in satisfactory condition Sunday, Harborview Medical Center spokeswoman Susan Gregg said.
Killed was 32-year-old S.J. Brooks, also of Seattle. "One person was reported to have swung their bike at the animal and scared it off for a period of time", said Myers.
"When these young animals, particularly males, leave home to search for territory of their own, and encounter territory already occupied by an older male cougar, the older will drive off the younger one, killing it if it resists". One of the deputies fired a shot, scaring the animal away.