Tripwire announces plans for new free content for Killing Floor as well as upcoming paid DLC for the multiplayer zombie game. The announcement is accompanied by a batch of new screenshots, and here's word:

20 July 2009, Roswell, GA: Tripwire is happy to announce details for the upcoming “Heavy Metal” free content pack for their hit co-op zombie shooter, Killing Floor. This first of many free updates planned for Killing Floor adds an all-new map, new weapons and new functionality and will be available to anyone that owns the game.

The new level, entitled “Foundry”, is set in an old iron works which the Horzine Corporation has converted to support their top secret military projects. Exactly what they have been up to here is a matter for conjecture – but before we can send in investigators, your squad has to get in there and clean out the infestation of specimens.

To assist in your task, there are now two new weapons. The first is an old favorite of armed forces the world over: the AK-47. In our case, it has the folding stock, for ease-of-use in close quarters. This one will fit in as a heavier weapon for the Commando Perk and provide extra stopping power over the base Bullpup. The second is a weapon that just about every special-forces soldier in every movie seems to know intimately, for no good reason other than personal interest: the Japanese Katana sword. Just where the squad got hold of it is a mystery, but this piece of Samurai history is just so fitting, such a thing of beauty and such a perfect melee weapon, that we aren’t going to ask too many questions.

In addition to this free update, Tripwire Interactive will be releasing our first paid DLC character pack for Killing Floor very soon. This character pack adds four new playable characters including a Horzine foundry worker and a soldier in prototype Horzine body armor.

Killing Floor is available now on Steam (www.steampowered.com) and will be in stores across the world shortly.