Two police officers and several firefighters were injured in an explosion at an apartment building in the western German town of Ratingen on Thursday, said the state interior ministry.
Police and firefighters were called to aid a helpless person and, when they arrived, there was an explosion at the door to the apartment, said a police spokesperson.
It was unclear what caused the explosion, said police and the interior ministry for the state of North Rhine-Westphalia.
A large-scale police operation was underway, the ministry said.
Broadcaster ZDF reported that 10 firefighters and 2 police officers had been injured, and security sources could not rule out a targeted attack.
At around 0800 GMT, the apartment owners' association notified police that the mailbox of one of the residents was overflowing, ZDF reported, citing the state interior minister.
Police then called in firefighters to open the door to the flat where a mother and her son were living, and there was a fire in the room, the broadcaster reported.
Interior Minister Nancy Faeser was set to make a statement on the incident in the afternoon, ZDF said.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
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