Howie Mandel back at work, says he's fine

LOS ANGELES - Howie Mandel is back at work and says his heart and health are fine.

The 53-year-old comedian was hospitalized in Toronto earlier this week following an outpatient procedure for an irregular heartbeat. Mandel said he returned to work Wednesday on his NBC hidden-camera show, 'Howie Do It!'

Mandel said he learned of his irregular heartbeat after a physician on the set checked his heart with a stethoscope. An electrocardiogram showed an irregular heartbeat, and doctors suggested an outpatient procedure.

Knoxville takes inert grenade to LA airport

LOS ANGELES - Authorities detained Johnny Knoxville on Thursday for allegedly bringing an inert grenade into Los Angeles International Airport.

After security screeners spotted the grenade in the 'Jackass' star's carry-on luggage, a bomb squad determined it lacked a firing pin or explosive. Police say Knoxville was later released and allowed to board an American Airlines flight to Miami.

Prosecutors will decide whether to charge the 38-year-old with bringing a prohibited item into a secure area of the airport, a misdemeanor.

Knoxville, whose real name is Philip John Clapp, told officers the grenade was a prop he forgot to remove from his bag, Airport spokeswoman Nancy Castles said.

Piven defends poisoning story

NEW YORK - Jeremy Piven is defending his reputation against skeptics who think he used mercury poisoning to get out of the Broadway revival of 'Speed-the-Plow.'

On ABC's 'Good Morning America' Thursday, Piven said he had been suffering high levels of mercury, six times the normal limit. The 43-year-old actor said he was diagnosed with mercury poisoning the first week of rehearsals for the play, and finally succumbed to the illness when he passed out in his home.