Staff and Wire Report

Police in Munich warned of a "serious, imminent threat" by Islamic State group suicide bombers wanting to commit a terror attack on New Year's Eve and asked people to stay away from the city's main train station and a second train station in the city's Pasing neighborhood.

Police tweeted that the city's main station and another had been evacuated. They warned residents to stay away from both locations.

In a Facebook post, authorities said they had "serious information" that the attack had been planned for New Year's Eve.

Bavaria's Interior Minister Joachim Herrmann told reporters Friday night at Munich's police headquarters authorities had received information that the terror group Islamic State was behind the threat.

Munich police president Hubertus Andrae said German authorities had been tipped off by a foreign intelligence service that IS was planning attacks with five to seven suicide bombers, the German news agency dpa reported. Andrae said so far there hadn't been any arrests.

Police spokesman Werner Kraus told The Associated Press that "after evaluating the situation, we started evacuating the train stations and also asked partygoers to stay away from big crowds outside."

The warning came only hours before the city rang in the new year.

Despite police warnings to stay away from big crowds, thousands of people were on the streets of Munich at midnight to welcome the new year with fireworks.

Cities across Europe are already on a heightened state of alert.

"There is the danger of an attack in the area of munich, please keep away from crowds, avoid the central station and the rail station pasing," police said in the tweet.

No details of the threat were provided, but police told NBC News separately that the main Munich Hauptbahnhof and Pasing train stations were evacuated, NBC News reported.

Shortly after the new year began at midnight (6 p.m. ET Thursday), police reiterated the warning on Twitter: "We expressly point out again that we take the threat very seriously! Please stay vigilant! #Munich"

A few minutes later, they began issuing the statement in other languages, NBC reported. High-profile attacks claimed by Islamic State and other groups this have cast a shadow over New Year's Eve gatherings around the world.