MADRID (AFP) - Spanish police have discovered a body resembling that of an American pilgrim who disappeared in April along a popular hiking trail and have arrested a suspect, the interior minister said Saturday.

Denise Pikka Thiem, 40, disappeared in April while hiking alone along the Camino de Santiago (Way of Saint James) pilgrim trail in northwestern Spain.

The remains "seem to correspond to those of Denise and the man arrested yesterday (Friday) could be the perpetrator," Interior Minister Jorge Fernandez Diaz told reporters.

The last time Thiem made contact with anyone was on April 4 when she sent a message to a friend saying she was at a point on the trail near Astorga in Galicia.

Police had on Friday confirmed arresting a suspect a day after resuming their search for her near Astorga, deploying 300 officers backed by a helicopter and search dogs with a focus on local wells.

"A person has been arrested and the search has been suspended for the moment," a police source told AFP, without giving further details.

The man was arrested at a property not far from Astorga following an order from a judge at a local court, a statement said, without giving details of his identity.

"The suspect led the police to a body in an advanced state of decomposition hidden under branches," it said.

"Pending an examination, it appears that the body is that of the American pilgrim," it added, indicating that an autopsy would be carried out in a nearby town.

Spanish police had previously questioned people Thiem had met while in Spain in an extensive operation involving around 200 people of 20 different nationalities, the minister said.

Hundreds of thousands of tourists and Roman Catholic pilgrims hike the Camino de Santiago each year, staying at hostels along their way towards the city of Santiago de Compostela.

Last month, Spain's Prime Minister Mariano Rajoy wrote to Thiem's parents saying he "understands the pain of a family that does not know where their daughter is", in a letter dated August 24 and seen by AFP.