A spokesperson for the firm, majority owned by China's Geely Holding, said it had been approached by a third party, but declined to give any further details.

"Investigations so far confirm that a limited amount of the company's R&D property has been stolen during the intrusion," the Swedish carmaker said in a statement.

It added that "there may be an impact on the company's operation", without specifying what that might be. It said it did not see an impact on the security of its customers' cars or their personal data.

The Gothenburg-based company said it had implemented security countermeasures to prevent further access to its property, while notifying relevant authorities.

"Volvo Cars is conducting its own investigation and working with a third-party specialist to investigate the property theft," it said.

Shares in Volvo Cars, whose IPO on Oct. 29 was the biggest in Europe this year, were down 3.2% at 1555 GMT.

(Reporting by Helena Soderpalm; Editing by Simon Johnson and Mark Porter)