Town halls in several German cities were evacuated on Tuesday after threats, in some cases bomb threats, were received by email overnight, a number of police forces said.

"A threat against the city of Augsburg has been received, the town hall has been cleared, we are investigating," tweeted police in the southern city of Augsburg.

Speaking to NBC News, a police spokesman in Augsburg said the email is "analogue to those received" in other cities, as the "content of the mail is identical."

Police posted similar tweets from western Neunkirchen and Kaiserslautern, eastern Chemnitz and central Goettingen.

Police in the southwestern city of Kaiserslautern told NBC News that an employee of the city hall found an email in the "general email box" this morning at 8:00 a.m. local time, in which an unidentified sender had claimed that "an explosive device had been deposited in the building."

Police immediately decided to evacuate the 21-story high-rise building and are presently searching the premises.

Police officials in the city of Goettingen also told NBC News that they had received an email claiming that an explosive device had been planted at the town hall. The building has been evacuated and the surrounding streets have been cordoned off.

"We are now trying to identify, who sent these emails and are coordinating our investigation with officials in other German cities, which also received these threats," a spokesperson told NBC News.

In Chemnitz, a police spokeswoman said that the search of the multi-story town hall building is ongoing.

A police spokesman in the northern German city of Rendsburg also confirmed to NBC News that the local town hall was evacuated this morning, a building search with experts is ongoing. A similar statement was made by a police spokesman in Neunkirchen in the state of Saarland.