Valve’s Gabe Newel has confirmed that the company’s game client Steam has become the victim of a cyber attack, allowing hackers to obtain the personal information of users of its digital download service.

In a statement issued on the official site, Newell apologised and advised Steam users to keep an eye on credit-card activity for any dubious transactions. The attack was carried out on November 6 when hackers compromised the site's forums, as well as a database containing user names, passwords, email address and encrypted credit-card information.

When logging back onto the forums, all users will be required to re-set their passwords, and Valve has advised people to change passwords of other accounts where the same details are used.

This year the gaming industry has been plagued by hacking attacks. In May, the PlayStation Network was subject to a large-scale security breach that saw hundreds of thousands of accounts compromised. That was followed by attacks on Codemasters Online Gaming, Bethesda, Epic Games, Sega and Bioware.

Currently the Steam forums are down while Valve investigates further.