Dead Island has sold over five million copies, Koch Media has announced.

That's global sales of the retail and digital versions since the game launched in September 2011. Koch, parent company of Dead Island publisher Deep Silver, said the zombie kill 'em up still enjoys strong sales today.

Koch boss Klemens Kundratitz gushed: "While others focus on ever-increasing development budgets and driving brand messages via ballooning marketing expenditures, Deep Silver stands for hitting the zeitgeist, innovation and fresh gameplay.

"Dead Island has an incredibly active and enthusiastic community, and we are thrilled to welcome the five millionth player to the world of Banoi. This once again proves that venturing into new waters in terms of games publishing does matter for success and that even at the end of a console cycle new IPs can be created and nurtured into lasting franchises."

Koch's commercial director Menno van der Bil said sales of Dead Island were a "good omen" for projected sales of follow-up Dead Island Riptide, due out in April.

"The continued success of Dead Island has proven that we're on the right track with our overall IP strategy for Deep Silver," he said. "Further new IPs with an innovative angle and maybe even surprising touch can be expected from Deep Silver."

Koch recently beefed up its portfolio with the purchase of the Saints Row IP and the publishing rights to Metro: Last Light from now defunct publisher THQ.