(CNN) An 8-year-old boy was seriously injured in a mountain lion attack in a Colorado backyard, wildlife officials said Thursday

The boy and his brother were playing outside on the trampoline Wednesday evening in Bailey, southwest of Denver, when the 8-year-old heard a friend calling him from the neighbor's house, the Colorado Parks & Wildlife said in a news release.

The lion attacked the child, biting him on his head as he ran to visit the friend, officials said.

We can confirm this is a mountain lion attack on a young boy. Wildlife officers are searching the scene. A dog team has been called in to help search the area for the mountain lion & because of that Bailey residents are asked to please keep their pets indoors. — CPW NE Region (@CPW_NE) August 22, 2019

The boy's brother ran inside and told his father something sounded off.

Wildlife officers set a trap near the scene of the mountain lion attack in Bailey, Colo., Wednesday evening. A dog team was also used overnight trying to track down the mountain lion from the attack. Efforts are ongoing Thursday to locate the mountain lion. pic.twitter.com/OBWr2efQj2 — CPW NE Region (@CPW_NE) August 22, 2019

"The father rushed outside and found the mountain lion on top of his son. The mountain lion let go of the child as the father approached and took off running," officials said.

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