Czech art activists scale Prague Castle walls to replace the President's flag with a huge pair of pants

Art group Ztohoven intended the stunt as a protest against President Milos Zeman

This huge pair of pants was hoisted up the flagpole on Prague Castle (Ztohoven/EPA)

Activist artists in the Czech Republic have hoisted a giant pair of red underpants up the flagpole of Prague Castle, in a protest against the country's President, Milos Zeman.

As reported by the Prague Post, the group of three men from the Ztohoven art collective climbed onto the roof of the President's office in Prague Castle, under the guise of chimney sweeps.

Once on the roof, they lowered the Presidential flag and replaced it with the giant pair of pants.

On their website, Ztohoven released a statement, saying: "Today we hung a banner over the castle for a man who is not ashamed of anything."

The statement also included a short poem that criticised President Zeman for his close ties to China and Russia.

The pants were quickly removed by security after the stunt, and the three men were arrested.

Police spokeswoman Andrea Zoulova said that three people had been detained on suspicion of disorderly conduct and theft, but were released while the investigation continues.