The head of Indian cricket's anti-corruption watchdog said on Friday Britain's extradition of accused match-fixer Sanjeev Chawla was "a legal landmark".

Chawla, one of the central figures in the scandal surrounding the late Hansie Cronje, was sent back to India on Thursday after spending four years fighting extradition. It is the first time India has managed to get an accused individual from the cricket gambling underworld sent back for trial.

Delhi police filed charges against Chawla and five others including former South Africa captain Cronje in 2013. Chawla is alleged to have conspired with Cronje to fix matches in South Africa's tour of India in 2000.

After his arrival, a Delhi court ordered Chawla to be held in custody for 12 days for questioning. He has challenged the order at the High Court. "It is a legal landmark," Ajit Singh, chief of the anti-corruption unit of the Board of Control for Cricket in India (BCCI), told AFP of the latest legal outcome.

"Extradition is a difficult process. All sorts of objections were raised, to the extent of threat to life of the accused and even the conditions of the Indian prisons. And this one is the first for match fixing."

Singh said his unit would ask to interview the 50-year-old Chawla and he had asked Indian police "to share anything, any information pertaining to cricket given to the police by Chawla."

Indian cricket has been hit by regular scandals in recent years. Two former Indian Premier League players are among six arrested last year accused of fixing a final of a regional Twenty20 tournament.

Delhi police had been investigating an extortion complaint when they stumbled upon a telephone recording that eventually led to the unearthing of the Cronje scandal that shook the whole sport. Cronje, who initially denied fixing charges, confessed his role in a tearful submission to an inquiry in South Africa. He was subsequently banned for life and died in a plane crash in 2002.