The BBC's 'Top Gear' is once again embroiled in controversy after the famous hosts were shown performing a drive-by shooting of The Stig. The stunt aired on Tuesday evening (December 21) during the first of two Christmas specials, involving a trip across the US. The episode has been slammed by some viewers and the BBC has admitted that it has received a 'considerable number' of complaints. TV regulator Ofcom has confirmed that it has also been contacted, and will investigate in due course. The stunt follows the controversial sacking of Ben Collins as the Stig in September after he wrote a book that revealed his identity. The 'Top Gear' presenters were shown firing at a cardboard cut-out of the Stig from a moving car. Complaints appeared on the BBC's Points of View online message board immediately after the programme was aired. One viewer said that he'd: "Turned off the programme in disgust." However, plenty of users reacted in defence of the programme. This isn't the first time that 'Top Gear' has courted controversy. Some claim the show is deliberately engineered to garner publicity, as this controversy comes two days before the second 'Top Gear' Christmas special, on Boxing Day. The show isn't struggling for ratings, though. Tuesday's special was watched by 5.41 million viewers - more than twice the amount that watched Jamie Oliver's Best Ever Christmas on Channel Four (2.11 million).