VIDEO: Tourist trapped in London bookstore

LONDON (WPVI) -- An American tourist took to Twitter after he got locked in a London bookstore for several hours.

David Willis said he went into the store in Trafalgar Square to use their Wi-Fi.

But when he was finished, he came down the stairs to realize he was trapped so he sent a message to the store on Twitter.

The post was re-tweeted more than 9,000 times.

Others replied with book recommendations

"I was too scared to touch anything I didn't want them to think I had hid in the store," said Willis.

But Twitter did the trick.

Police and a store manager soon arrived and freed Willis after 2 and a half hours.