A Canadian citizen has been extradited from London to the United States to face charges that he helped arrange trips to Thailand for adults who paid to have sex with children there.

John Wrenshall was arrested in London in December 2008.

The 62-year-old faces three charges related to sex tourism and more than a dozen counts of charges related to child pornography. 

Wrenshall lived and worked in Calgary 12 years ago. He was convicted in 1997 of sexual assault involving members of a Calgary boys' choir.

The sex tourism charges carry a maximum sentence of 15 years each. Sentences for the child pornography charges range from 10 to 15 years.

Some of Wrenshall's clients have already pleaded guilty.

Wrenshall is scheduled to appear in U.S. District Court in Newark, N.J., Tuesday afternoon.

It was not known if he had retained an attorney.

With files from The Associated Press