Image caption Police are uncertain whether it was a random robbery

A Pablo Picasso drawing, thought to be worth £100,000 has been stolen from an art gallery in San Francisco.

Police are looking for a man who walked into the Weinstein Gallery and took the valuable pencil drawing off the wall and then fled in a taxi.

A gallery spokeswoman told the San Francisco Chronicle newspaper that the work was an "original and unique" artwork.

It is thought Picasso created Tete de Femme in 1965.

Speaking to the newspaper, police spokesman Officer Albie Esparza said: "We're hoping someone in the public might recognise this piece, if they see someone walking around with it or trying to sell it.

"We don't know if the place was targeted or whether this was a random opportunity that this guy took advantage of."

Other artists whose works are still on display at the gallery include Marc Chagall, Salvador Dali and Joan Miro.

Last year five paintings by Picasso, Matisse and other great artists were stolen from the Museum of Modern Art in Paris.