Image copyright AFP Image caption The painting was auctioned in Hong Kong, where demand for art is increasing fast

Hong Kong police are investigating the disappearance of a painting worth $3.7m (£2.2m) from a hotel, amid reports it may have been accidentally thrown away.

The painting is believed to be a Chinese ink work by artist Cui Ruzhuo entitled Snowy Mountain.

It was reported missing by auctioneers Poly Auction on Tuesday, having been successfully sold on Monday.

Several local media reports suggest cleaners at the Grand Hyatt could have thrown the painting out as rubbish.

According to the South China Morning Post, CCTV footage showed a security guard kick the packaged painting over to a pile of rubbish.

Citing a police source, the paper said that cleaners were then seen throwing the rubbish away, with the rubbish taken to landfill.

In a statement, the hotel said it was working with investigators.

"As the organiser has rented our event venue for this auction, Grand Hyatt Hong Kong is doing its best to offer assistance to Poly Auction including letting the police view the CCTV footage along with our security team," it said.

The hotel said the auctioneers were responsible for items they sold.

Police have found no trace of the painting, which could now be one of the most expensive pieces of rubbish ever.