By Tom Mustin

HIGHLANDS RANCH, Colo. (CBS4) – A 13-year-old is still recovering after being attacked by a dog while jogging a week ago.

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“I checked to see if I was bleeding and I was,” Luke Sorensen told CBS4’s Tom Mustin.

Luke Sorensen (credit: CBS)

The Highlands Ranch eighth grader is on the cross country team at Mountain Ridge Middle School. On June 5 the team had been practicing at the popular Red Tail Park when Luke ran past a man and his dog.

“I passed a guy walking a German shepherd. Right when I passed the German shepherd he bit me on the butt.”

Luke Sorensen’s injury (credit: CBS)

Luke says he realized he was hurt and bleeding, but the man took off.

“The guy walking the German shepherd just jogged away and mumbled, ‘I’m sorry,'” he said.

Luke takes blood thinners for a heart condition. He went to the hospital and received stitches and antibiotics. His mother, Cathy Sorensen, said her son was lucky.

“He bleeds very easily,” she said. “This could have been a lot worse. If this had been a smaller child this dog would have bitten him in the face, and that’s not okay.”

Cathy says a week after the attack, the dog’s owner has still not come forward.

A man walking a dog at Red Tail Park on Monday. (credit: CBS)

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“It’s disappointing. You teach your kids right from wrong. You know you’re in the wrong if your dog is biting someone and you take off. At least give us your name and number so we can have a conversation to know if the vaccinations are up to date,” she said.

CBS4’s Tom Mustin interviews Luke and Cathy Sorensen (credit: CBS)

Animal control officers say reports of dog incidents on Highlands Ranch trails occur almost daily. They say pet owners need to watch their animals and keep them on a leash.

Officials with the Douglas County Sheriff’s office are looking for the German shepherd responsible for the attack, as well as its owner. They say that was a man with a dark tan wearing a black baseball cap. The dog was described as being a thin, black and tan German shepherd.

Cathy and her neighbors are also on alert.

“Whenever I’m out driving I’m looking for someone with a German shepherd. I’m not saying the breed is bad, I’m saying what happened is a terrible thing and we’d just like some answers,” Cathy said.

Red Tail Park (credit; CBS)

As Luke recovers from a frightening attack, he and his family have learned a painful lesson about the scenic trails in Highlands Ranch.

“I thought the most dangerous things on the trails were rattlesnakes. I was wrong,” said Cathy.

Luke will have his stitches removed Wednesday. He’s already back and running on his cross country team.

Anyone with more information about the dog attack is asked to call the Douglas County Sheriff’s office at (303) 784-7880 or animal control at (303) 660-7529.

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Tom Mustin is CBS4’s Weekend Anchor. He has been with CBS4 since 2002, and is always looking for great story ideas. Connect with Tom on Facebook or follow him on Twitter @TomCBS4.