WASHINGTON (Bloomberg) - The United States Justice Departmentwill dispatch a team to Turkey in coming days to pursue allegations by the Turkish government of criminal activity by cleric Fethullah Gulen, an Obama administration official said on Friday (Aug 19).

Turkish President Recep Tayyip Erdogan has demanded that the US extradite Mr Gulen, a 75-year-old Muslim scholar who lives in rural Pennsylvania, after a failed coup attempt in July by elements of the Turkish military. The extradition request was discussed by the US official, who briefed reporters on the condition of anonymity, ahead of a visit to Ankara on Aug 24 by Vice-President Joe Biden.

While Turkey has repeatedly blamed Mr Gulen for the attempt to overthrow the government - and has jailed thousands of his alleged followers and allies within the country - they have not presented formal evidence to the Justice Department so far that he was involved in the coup attempt, the official said. Instead, the evidence focuses on alleged plotting and criminal behaviour by Mr Gulen before the coup.

Mr Erdogan has personally lobbied President Barack Obama to turn over Mr Gulen, an ally turned enemy. Turkey says Mr Gulen's movement, which includes an international network of schools, charities, and businesses, is a terrorist organisation.

But the Obama administration has said Turkey needs to provide clear evidence of criminal activity to satisfy US due process requirements as well as provisions of the US-Turkey extradition treaty.

Sending the Justice Department team may be intended to assure Mr Erdogan that the US is taking the extradition request seriously. On Thursday, Mr Erdogan admonished the US, saying that as a strategic partner the country should turn over the cleric.

Mr Gulen has denied involvement in the coup while criticising Mr Erdogan for what he calls authoritarian tendencies.