Former world heavyweight champion Mike Tyson has arrived in the UK for his controversial fight against Britain's Julius Francis.

He was met at Heathrow Airport by a scrum of fans and journalists so huge that a tabloid reporter was knocked down in the chaos and taken to hospital.

The female journalist, who works for The Mirror newspaper, was treated with oxygen before being driven away in an ambulance, but was not badly injured.

Fight promoter Frank Warren said he was "delighted" by the welcome, saying he had "never experienced anything like it".

"That was bigger than when Mohammed Ali came over," he said. He added that Tyson had also been "overwhelmed".

Tyson, surrounded by minders, airport officials and police, was quickly whisked off to the luxury Grosvenor House Hotel in Park Lane, central London.

BBC correspondents said he and his entourage, numbering about 30 in total, have taken up a whole floor of the luxury hotel, hiring five suites at a cost of £750 per suite per night.

A gym has been installed for Tyson, who is expected to stay in the hotel until next week.

On Sunday evening he went for a short walk, visiting the nearby McLaren car showroom for a spot of window-shopping with Mr Warren.

One of his friends said Tyson was in bed by 2030 GMT on Sunday evening.

Former champion boxer Lloyd Honeyghan added: "He's in better shape than I've seen him for 10 years. I can never remember seeing Mike Tyson in such a good frame of mind."

Asked about the controversy surrounding the American's visit, Honeyghan said: "There's no controversy ... Tyson loves Britain and the people over here."

But as Tyson slept, the argument raged on over whether Home Secretary Jack Straw should have allowed the boxer, convicted of rape in 1992, into the country.

Anti-rape campaigners said they would go to the High Court on Monday to challenge Mr Straw's decision, saying he went beyond his powers in setting aside immigration rules on foreign criminals.

The rules ban people convicted of crimes that would carry a prison sentence of more than 12 months in Britain, except on "compassionate grounds".

Mr Straw had said the investment made in the match by Manchester firms and other British businesses created "exceptional circumstances" which allowed the regulations to be set aside.

But Justice for Women spokeswoman Julie Bindel said: "The majority of British people don't want Tyson here.

"What message is Jack Straw sending to men and boys in this country who look up to Mike Tyson?

"Jack Straw's department is responsible for implementing the national strategy on violence against women and his decision is at odds with that role."

If the group is successful in its appeal, the sell-out fight, to be held on 29 January at Manchester Arena, would be cancelled.

Mr Warren said the reaction from the public to Tyson's visit had been "overwhelmingly positive", and that he had not received any letters of complaint.