Two pieces of graffiti originally painted on the side of a trailer fetched nearly £100,000, auctioneers said.
Border Auctions said the works had been created by graffiti artist Banksy at various music festivals in the late 1990s.
Staff said one piece called “Drums/Grenade” fetched £38,000 at a sale in Hawick, Roxburghshire. A second, called “Sid Vicious 100% PunkRock” went for £58,000.
The auction house said Banksy, whose identity is shrouded in mystery, painted the works on a wooden trailer at a festival nearly a decade ago.
A spokesman said trailer owners Nathen Wellard and Emma Neale had decided to sell and the works had been cut from the trailer and placed in Perspex boxes.
He said the couple, who live near Downham Market, Norfolk, were friends of Banksy, who is renowned for creating graffiti on city buildings.
“These early examples of his work are quite different from the more well known urban, stencil work often created at night,” said the spokesman.
“What makes them special is that they were created very much in the midst of a festival and can be viewed as examples of performance art by the artist.
“The concept of ‘performance art by Banksy’ is virtually unknown to the media and general public alike and these works are probably some of the first to come to auction.”
Border Auctions’ director Maurice Manning said both pieces had been bought by anonymous buyers in telephone bids.
