ARCHAEOLOGISTS re-excavating an ancient roman room were surprised to discover parts of it missing today.

The team were left searching for answers when they discovered the mosaic tiles, dating back to the second century, were no longer there.

Simon West, archaeologist for St Albans District Council, believes the tiles, once part of a manor house still buried under ground, could have been sold by its discoverer in the 1930s.

Simon and his team of experienced volunteers began digging up the room next to the Hypercaust building in Verulamium Park on Monday.

He said: "The room was first discovered in the 1930s with details and drawings taken of the room. We wanted to find out if anything had changed naturally and take our own modern reports of the room.

"We have fulfilled our brief, however in quite a negative way.

"It was certainly a surprise to find it was no longer there.

"There's a possibility he may have sold the mosaics to the public, which isn't a criticism of him but it wouldn't be allowed today."

It could be that the mosaic was used to complete another section elsewhere, but Simon admitted that would probably have been put on record.

The dig purposely coinsides with National Archaeology Week with the public invited to watch the experts at work today and tomorrow.

The Young Archaeologists Club were also helping out with the excavation work, the first undertaken in around 10 years.

Special free activities are also on at the St Albans Museum including a "sand dig" where children can discover old coins, special displays of bones and ancient Roman objects and workshops to join in.