If Kanye West jumped into a lake, would you jump too?

Police had to shut down Kanye West's impromptu free concert in the Armenian capital of Yerevan early Monday after the U.S. rapper jumped into a lake, inspiring dozens of fans to follow.

"We're going to do something different right now," the 37-year-old performer of Yeezus exclaimed before leaping into a shallow pond known as Swan Lake.

Within moments, a swarm of fans watching from the other side also jumped into the water, with some getting too close to the American star.

Kanye West, third from the right, smiles as he's escorted out of Swan Lake by security guards and policemen early Monday morning. (Vahan Stepanyan/PAN Photo/Reuters)

Police and West's security staff quickly leaped into action, escorting the rapper to safety, pushing at least one eager concertgoer out of the way in the process.

West's wife, reality star Kim Kardashian, had announced the free concert to her 31 million followers on Twitter.

According to her, thousands of people turned out for what became a "crazy night."

Can't see the tweet? See it here.

The surprise concert was the last event on an Armenian tour by Kim Kardashian and family.

West and Kardashian were joined by daughter North and sister Khloe for a four-day visit to the Kardashian ancestral homeland.

US reality TV star Kim Kardashian, centre, and her rapper husband Kanye West (third from the left) visit the genocide memorial, which commemorates the 1915 mass killing of Armenians in the Ottoman Empire, in Yerevan on April 10, 2015. (Karen Minasyan/AFP/Getty Images)

The tour included a visit to a complex created in memory of the estimated 1.5 million Armenians killed by Ottoman Turks around the time of the First World War.

The famous family is now in Israel for what was described as a private two-day visit.

They are expected to shoot some footage for their reality show in Jerusalem before moving on to Jordan.