Angry Birds maker Rovio Entertainment fell short of market expectations for quarterly sales and profit, sparking a near 20% fall in the Finnish firm's shares. 

Increased marketing costs meant adjusted earnings before interest, tax, depreciation and amortisation were flat at €8.6m in the third quarter.

But sales rose 41% from a year ago to €70.7m.

Rovio, which was listed on the Helsinki bourse in September, saw its shares drop by almost 19% - well below its IPO price of €11.50.

Rovio saw rapid growth after the 2009 launch of the original "Angry Birds" game, but it plunged to an operating loss and cut a third of its staff in 2015 due to a pick up in competition and a shift among consumers to freely available games.

Rovio's game titles now include "Angry Birds 2," "Angry Birds Blast", "Angry Birds Friends" and "Battle Bay."