German police Friday lifted an alert of an imminent attack in Munich, hours after two key train stations were evacuated over fears that a New Year suicide bomb assault was being planned.

"Overall I would say that the situation for Munich is as it was before this threat of attack," the southern city's police chief Hubertus Andrae told journalists.

In a security update, Munich police also issued a statement saying that "following investigations, there is currently no concrete risk of an attack" in the city.

Police had issued an alert late Thursday following a tip-off from a foreign intelligence service that suggested an assault was being planned for midnight.

Andrae said investigators had in hand names of "half of the five to seven" suspects who were allegedly planning to blow themselves up at locations including Munich's main rail hub and Pasing station in the western part of the city.

"We have examined data relating to these names, but at the moment, we do not know if these names are correct, whether these people exist and where they are," he said, adding that the suspects were allegedly from Iraq and Syria.

Andrae refuted speculation that the threat was a false alarm, saying that "if there is such information, we have to act".