BERLIN, April 21 (Xinhua) -- The German city of Trier has been selling thousands of zero-euro souvenir bank notes recently to celebrate the 200th birthday of Karl Marx on May 5.

The bills, sold at 3 euros each, have drawn a sizable number of buyers around the world. The first batch of 5,000 notes were sold out after going on sale on Monday, and the city is now printing 20,000 more.

The bank notes, printed in purple, look like genuine euros but are labeled "souvenir."

The bills play on Marx's criticism of capitalism, said Norbert Kaethler, managing director of Trier's tourism and marketing office.

Karl Marx, a famous German philosopher, economist and political theorist, was best known for his works such as Das Kapital, and the Communist Manifesto, which was co-written with Friedrich Engels and has been serving as a guiding principle for the Communist movement.

Besides selling souvenir bills, the city, which witnessed Marx's childhood and early education, has also planned other events and celebrations, including a grand state exhibition.

Trier is also unveiling a 4.4-meter bronze statue of Marx, which was presented by China as a gift to the great thinker's hometown.