American magician David Blaine has unveiled his latest crazy stunt in New York's Central Park.

American magician David Blaine has unveiled his latest crazy stunt in New York's Central Park.

Two hours after being hoisted upside-down, Blaine looked uncomfortable. He could be seen stretching his legs and pulling himself up to a horizontal position about every five minutes.

He said this challenge where the blood rushes to his head for a prolonged period has been particularly difficult.

David Blaine said, "I think the hardest part of this is going to be sleep-deprivation plus keeping blood flow and I guess the good news is, I guess the other factor that we didn't consider is heat from the sun. That'll need to be considered."

Blaine's doctor said he is particularly concerned about blood clots and blindness.

Ronald Ruden, Blaine's doctor, said, "We get into real trouble because if he throws a clot or he breaks a blood vessel in his brain, there is nothing stopping it. So we just have to hope it doesn't happen because if it happens it will literally be a tragedy for David."

Blaine's past challenges include holding his breath under water for more than 17 minutes, fasting for 44-days while suspended in a glass box over the Thames in London, and surviving in a block of ice for more than 60 hours. With each challenge, he takes things minute by minute, and does not contemplate the remaining time he must spend in discomfort.

(CCTV September 24, 2008)