BERLIN (Reuters) - German police are investigating 16 people suspected of shouting a Nazi slogan in a Munich beer garden, the police said in a statement on Wednesday.

On Tuesday evening, a 26-year-old man was reported to have displayed a gesture and chanted a slogan related to "prohibited organizations", and the rest of the group reportedly joined in, the police said.

Local TV station Bayerische Rundfunk reported that the group shouted the Nazi slogan "Sieg Heil" several times, citing a witness.

The police did not immediately respond to a request for further information.

In Germany, the use of slogans and symbols linked to anti-constitutional groups, including the Nazi party, has been illegal since World War Two.

Recently, Germany has been shaken by several racism-related incidents as the far-right party Alternative for Germany (AfD) has gained popularity, especially in the eastern part of the country.

Those include a group of young people caught on video chanting "foreigners out" in an exclusive club on the island of Sylt, and a senior AfD figure being fined by a court for using a Nazi paramilitary slogan.

(Reporting by Andrey Sychev; Editing by Ludwig Burger and Christina Fincher)