PARIS, Sept. 8, 2006 Human error led to the shattering of a fragile artwork on loan from the United States, while the reason for the loss of another piece was unknown, Paris' Pompidou Center said yesterday.

The Paris museum said that it took full responsibility for the lossesa 1971 untitled resin piece by Peter Alexander and a 1967 Plexiglas creation by Craig Kauffman called Untitled Wall Reliefthat were part of an exhibition on Los Angeles art from 1955 to 1985.

''We are dismayed to be unable to return them,'' said Pompidou Center President Bruno Racine.

Alexander's piece, on loan from New York's Franklin Parrasch Gallery, fell from the wall in early March, on the eve of the exhibition's opening.

An investigation showed that miscommunication between a restorer who installed the hanging system and the person hanging the work was to blame, the museum said. The restorer's instructions to let the glue stand for 24 hours were misinterpreted, and the artwork was fixed to the wall on the same day.

Kauffman's piece, worth $60,000, had been hung from a cornice while representatives of the Los Angeles County Museum of Artwhich loaned the piecewere present.

It fell and shattered in mid-July, just before the exhibition closed, though the cause of the accident remains unknown. Four visitors and a museum guard testified that no one touched the work before it fell, the Paris museum said.

''Despite a close and thorough investigation, the cause of the incident cannot be unequivocally determined,'' Racine said, though he offered two possible explanations.

There may have been an error in installation that became undetectable once the piece was hung, he said. Alternatively, a visitor may have touched the work, dislodging it.

''We will never know with certainty what really happened,'' Racine said.

Both pieces were insured, and the Pompidou has offered to pay for the artists to remake the pieces.

The Pompidou lends nearly 3,000 works of art every year and borrows just over 2,500.

''As a major lender and a significant borrower, we see there are 1 1/2 times more incidents on works that we lend than on those we borrow,'' Racine said. ''Nevertheless, these two incidents are two too many.''

by Aurelie Toulemond, Copyright 2006 Associated Press

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