More than 17,500 customers of London's National Theatre have been advised to reset their online passwords after the organisation's website was hacked.

A spokeswoman for the theatre said there had been a "security incident" which meant an "unauthorised user" accessed customers' online accounts.

But financial details of customers were not compromised as that information is encrypted, the spokeswoman said.

The website, which was hacked on 20 February, has since been secured.

In an e-mail to customers, the National Theatre said: "We were notified over the weekend of a security incident that took place on Saturday 20 February which may have led to your National Theatre website account - e-mail, password, name and contact information only - being accessed by an unauthorised user.

"Your payment information is safely encrypted, so no financial or booking details have been viewed.

"The affected system has been secured, however we would ask you to change your password on the National Theatre site."

The 17,500 customers are 3% of the theatre's registered members.

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