Jack Osbourne and his new wife Lisa Stelly (WENN.COM)

Newlywed reality TV star Jack Osbourne has been hailed a hero after helping to save a drowning woman who suffered a heart attack at sea.

Ozzy Osbourne's son, who wed his fiancee Lisa Stelly in Hawaii on Sunday, was on the beach with a friend when they spotted a woman in distress off the coast of the paradise islands.

Jack's new wife reveals they swam out to drag the lady to shore, and she's now recovering in hospital.

In a series of posts on her Twitter.com page on Tuesday, Stelly writes, "Really proud of Jack and his friend Tyler who saved a woman on the beach yesterday who'd had a heart attack and drown (sic). They resuscitated her until the ambulance came. We just found out she's in a stable condition! Awesome!"