ZURICH – Police were tightlipped Tuesday about reports that paintings stolen in one of Europe’s largest art thefts may have been discovered in a parking lot in front of a Zurich mental hospital.

Investigators promised to give an update later Tuesday about the search for the four Impressionist pictures worth CHF180 million that were stolen from a private museum in a February 10 armed robbery.

Police seized a white sedan parked at the hospital late Monday.

Swiss news media quoted unidentified eye witnesses as saying two or three of the pictures were seen on the back seat of the car, which caught the attention of the building supervisor of the Psychiatric University Clinic because the vehicle was unlocked.

A large police operation followed the discovery of the car, with the hospital grounds sealed off and forensic experts going over the vehicle meticulously before it was towed away.

Police had said initially that such a white vehicle may have been used by the three robbers when they made their escape with the four paintings by Cezanne, Degas, van Gogh and Monet from the EG Buehrle Collection.

The clinic was about 500m from the museum.

Interpol, which has been coordinating the international search for the paintings, said it was unable to comment on any developments because that would be up to Swiss authorities.

Zurich police spokeswoman Judith Hoedl, who confirmed that a suspicious car had been found at the clinic, declined to say more than that there might be a connection to the robbery.

The mass-circulation daily Blick and the local TV station TeleZuri quoted a witness as saying that the car contained three paintings bearing the name of the museum. The picture on top was Claude Monet’s “Poppy field at Vetheuil,” the witness was quoted as saying.

The other pictures stolen were Edgar Degas’ “Ludovic Lepic and his Daughter,” Vincent van Gogh’s “Blooming Chestnut Branches” and Paul Cezanne’s “Boy in the Red Waistcoat.”

[Copyright ap 2008]