The long awaited Doom 3 computer game is due for release in America tomorrow and in the UK next week. However a leak has led to the game being readily available over file-sharing networks in the Internet.

id Software, maker of the game could lose hundreds of thousands of pounds in sales. Thousands of people have been downloading Doom 3.

At one stage on Sunday 50,000 copies of Doom 3, which is 1.5 gigabytes, were being downloaded simultaneously. This amounts to $2.7m (1.5m) of lost sales.