Ian Smith is in critical condition after video shows him jumping from the roof during an afternoon pool party.

His brother says Ian has broken ankles, broken heels and multiple broken vertebrae in his lower back.

"Ugh, it definitely made me sick," Brittany Polliard, who witnessed the jump, said.

She saw a "pool of blood" after Smith's jump. Jared Roberts lives in the building that Smith climbed. Roberts says people were screaming, and when he looked up, Smith was on the roof. He says he turned away to avoid seeing the jump, but he heard Smith hitting the pavement.

"You could hear him hit it, and just kinda rolled into the pool," said Roberts.

Witnesses say some people were urging Smith not to jump, though some were encouraging him. Witnesses say people were drinking and lounging by the pool. Smith, they say, did not live in the Ram's Village apartment complex.

"When they realized how far he'd jumped from, one of the paramedics was saying he was lucky to be alive," Roberts said.

Witnesses say the student was helped out of the pool, and firefighters confirm an ambulance took him to Medical Center of the Rockies in Loveland.

Ram's Village is just blocks away from Ram's Pointe - the site of a mega party in the summer of 2011 - which ended with many students arrested and garnered national media attention.