(Cover) - EN Showbiz - Marilyn Manson insisted on singing a Justin Timberlake song six times at a karaoke bar.

The goth-rocker was in Las Vegas over the weekend celebrating Halloween. The star made an appearance at a party at The Bank nightclub, but wanted to continue the fun afterwards.

He reportedly consumed "numerous shots of absinthe" and then asked pals to go to a karaoke bar with him at 4am.

Marilyn was with his on/off partner Lindsay Usich and some other pals, and they eventually ended up in establishment Born and Raised.

"More shots followed, some shotgunned beers, before Marilyn got on the mike and sang The Doors' Texas Radio and a pretty-good version of Timberlake's Cry Me a River, which he sang six times," a source told New York Post.

The star was apparently adamant he wanted to sing Justin's track, and couldn't be placated even when staff said they didn't have the song.

"He was insisting on Timberlake music, so somebody had to download it on their iPod," another insider laughed.

The bar was putting on a Halloween bash when Marilyn, 42, turned up. Partygoers were amazed to see him joining in the fun, although things almost turned sour when the music "started crackling loudly".

"Marilyn was not happy," the second source explained. "He seemed aggravated and wanted to head back to the Strip. Then he got more annoyed when there was no car waiting for him outside."

The rocker then spotted an unmanned limousine and leapt into it. The driver was making a phone call, but spotted him immediately and managed to haul him out.

Marilyn's own car then arrived and he offered a reason for his bazaar behaviour. "I am sorry I went nuts, but I'm a rock star!" he screamed.

Marilyn was not available for comment. (C) Cover Media