Authorities in the United States have formally requested the extradition of a man described by the FBI as being the “largest facilitator of child porn on the planet”.

Eric Eoin Marques is wanted over four charges linked to website images described as being extremely violent, graphic and depicting the rape and torture of pre-pubescent children.

The 28-year-old, who has Irish and US citizenship, has appeared before the High Court in Dublin where extradition proceedings are under way.

Patrick McGrath, senior council for the attorney general of Ireland, said the accused was wanted in connection with the advertising, distribution and conspiracy to advertise and distribute child pornography.

The charges date from July 24, 2008 to July 29, 2013, two days before his arrest.

He is accused of being the sole administrator of a hosting server where multiple websites were held and where it is alleged pornographic images were shared.

If convicted in the US, he faces sentences of up to 30 years in prison.

The court heard a formal request for extradition has been received from the US and a certificate granted by Ireland’s Justice Minister Alan Shatter.

An FBI special agent previously told the court the suspect, who has an address on Mountjoy Square in Dublin’s north inner city, is accused of being “the largest facilitator of child porn on the planet”.

He has denied being the administrator of an anonymous hosting server.

Dressed in blue jeans and a grey Adidas track-suit top, Marques sat with three prison officers in courtroom number three in the Four Courts.

Members of his family were in the court .

Marques was arrested two weeks ago in the Irish capital on a provisional warrant and refused bail amid fears he was a flight risk and would interfere with evidence.

Mr Justice Nicholas Kearns, president of the High Court in Ireland, adjourned the case until September 11 and remanded Marques in custody.

Defence barrister Remy Farrell told the court he would apply for bail at the hearing.