A proud Dartford mum said she was blown away to find out her "genius" 11-year-old son had aced the British Mensa IQ exam earlier this month.

Safwaan Bhuiyan, 11, scored an impressive 162 in the prestigious exam, putting him in the top 1 per cent bracket of brainiacs in the world and well above the 'genius' score of 140.

Safwaan's mum, Munna, said her brainy boy has always been intelligent but never realised just incredibly smart he was until he breezed through the tough test on June 15.

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Speaking to News Shopper, Safwaan said he was "gobsmacked" after receiving his results, despite not preparing beforehand.

"I didn’t feel any pressure doing it, I just wanted to find out how intelligent I was.

"I didn’t study at all. Some parts of it were difficult but I felt confident that I could get through it," he said.

News Shopper:

Bright boy Safwaan with his younger sister at their Dartford home

However despite his massive intellect, a modest Safwaan said he avoided telling the majority of his mates that he was going to do the exam as he didn't want to come off as being boastful.

"I told some of them but I didn't like talking about it. I don’t want to boastful or arrogant," he said.

Speaking after, Mrs Bhuiyan said that although her 'genius' son is obviously very intelligent, he has yet to lose his great sense of humour or his love of football.

Safwaan is set to start as a Year 7 at Dartford Grammar For Boys this coming September and hopes to get into the aviation industry to design planes in the future.