Pieces of an ancient Egyptian necropolis that was pillaged in 1999 have been found in Spain by an expert in Middle Eastern antiquities who spotted them in a shop, Spanish police said Wednesday.

The eight pieces of limestone carry hieroglyphic inscriptions dating from the third century BC, police in the northeastern city of Barcelona said in a statement.

They were discovered by an expert from Barcelona University's department of Middle Eastern antiquities.

He spotted them in an antique shop and noticed they "bore inscriptions that made him suspect they came from" the Saqqara burial ground in the ancient Egyptian capital of Memphis, which was pillaged in 1999, the statement said.

The fragments were on sale for between 2,000 and 10,000 euros (2,600 and 13,000 dollars).

The shop's owner was unaware of the "illegal origin" of the pieces, which are to be returned to the Egyptian government, the statement said.