Telecommunications firm Telstra shut down its online billing and BigPond e-mail service for more than 24 hours starting Friday night after its bundle plan customer database became accessible to the public exposing user names and passwords of some 60,000 customers.

The lockdown to prevent hacking of email accounts drew complaints from customers. An estimated one million customers are believed to have been inconvenienced by the disconnection. Some tweeted that their business were affected and are planning to sue Telstra for damages or leave the network.

Telstra issued a public apology for the temporary shutdown.

"We apologise for the disruption and we know that they would want us to do everything we can to ensure and protect their privacy," Courier Mail quoted Telstra spokeswoman Karina Keisler as saying.

The breach of the internal website was reported by a customer after being directed to the open website while googling for a customer service phone number. Telstra immediately removed the website and disabled its online billing, BigPond self care and the My Account functions on its website.

Telstra is investigating the cause of the breach and has reported the incident to the privacy commissioner.
The Australian Communications Consumer Action Network said it will also investigate the breach.