The Spanish government on Thursday blocked the auction of a 17th-century oil painting in Madrid on suspicion that it may actually be a lost masterpiece by the Renaissance artist Caravaggio. Writing on Twitter, Culture Minister Jose Manuel Rodriguez Uribes said the painting had been declared "not for export... on suspicion it may be a Caravaggio". Entitled "Coronation with Thorns", the work shows Jesus before his crucifixion and in the auction catalogue is attributed to "the entourage of (Spanish artist) Jose de Ribera". alv/hmw/mg/kjl