A Spanish art dealer identified by authorities in the United States as a central figure in one of the most sweeping and stunning art swindles in the last decade has been arrested in Spain, and an Interior Ministry official there said Sunday that he expected the U.S. to request his extradition.

The art dealer, Jose Carlos Bergantiños Diaz, was arrested by the Spanish police Friday at a hotel in downtown Seville, according to the official, who is with the Spanish Interior Ministry in Madrid.

The official said Bergantiños, who suffered an anxiety attack after his arrest and was briefly hospitalized, was being held by the police in Seville.

But Bergantiños is likely to be transferred to Madrid in the coming days, the official said, where he will appear before a judge pending an expected extradition request.

Federal prosecutors and FBI agents in New York believe that Bergantiños carried out a daring forgery swindle that fooled the art world, leading collectors to spend more than $80 million on dozens of phony masterworks.

The swindle, officials have said, was carried out with Bergantiños’ girlfriend, Glafira Rosales, who pleaded guilty in September and has been cooperating with federal authorities.