PC maker Acer has confirmed that investigations are underway into a security breach of its European Packard Bell unit.

The breach was first reported earlier this month, when a hacking group called Pakistan Cyber Army claimed it had broken into an European Acer server and stolen the personal data of roughly 40,000 Acer customers.

The Taiwanese company said that only Packard Bell customer data was affected. It said that the investigation is ongoing.

"The information disclosed was limited to name, address, phone, email and system serial number. No credit card or other personal data appears to have been included," the company said in a statement.

Acer did not disclose the number of affected customers and provided no other information about the attack.