The sex play, which included Kinga simulating sex with a wine bottle and a plastic dog, was shown on Tuesday night's 'Big Brother' and by yesterday afternoon complaints to Ofcom had reached 83. Overnight this number soared.
The media regulator confirmed that it would be investigating the incident after Channel 4's 10pm round-up programme showed the newly introduced contestant Kinga, who arrived on Sunday to replace Orlaith, get down on all fours and simulate sex with a plastic dog, as well as what could be construed as masturbating with a wine bottle.
Kinga, dubbed the "Kinga the Minga" by tabloids, later drunkenly snogged Anthony and Craig and fondled the latter under the duvet.
Channel 4 defended the series, saying viewers were warned about the sexual nature of last night's show.
"Kinga's antics were broadcast well after the 9pm watershed and there was an introductory voiceover before the show alerting viewers to the sexual nature of the scenes," a Channel 4 spokeswoman said.
Channel 4 also pointed out that tonight's episode will follow on from last night's events with Kinga explaining to the housemates what she did not do with the wine bottle. She will deny she used the bottle to pleasure herself.
Meanwhile, Tory speechwriter Derek is the favourite to get booted out of the house on Friday as he is nominated for eviction alongside self-confessed geek and best pal Eugene.
'Big Brother' yesterday revealed that Derek and Eugene were up for eviction on Friday after receiving three nominations each. Makosi, Anthony and Craig all received two nominations.
Bookmaker Paddy Power has given Derek and Eugene odds of 1/3 and 2/1 respectively to get the boot, but said it is still anyone's game.
"The bookie doesn't always get it right -- last week Kemal had been a hot favourite to still be in the house rather than terrorising Dermot on 'BBLB'," Darren Haines, spokesman for Paddy Power, said.
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