Police in the German city of Braunschweig have cancelled a popular Carnival street parade because of fears of an imminent Islamist terror attack.

Police spokesman Thomas Geese said police received credible information that there was a "concrete threat of an attack" on Sunday's parade and therefore called on all visitors to stay at home.

Braunschweig's Carnival parade is the biggest one in northern Germany and draws around 250,000 visitors each year.

Geese said the parade was canceled only 90 minutes before its scheduled start and that "many people arriving at the train station were already dressed up and very disappointed -- but we didn't want to take any risks."

Carnival is celebrated in many regions of Germany with parades, music, revelers dressing up in costumes and dancing in the streets.