AT least 12 emergency workers have been hurt in an explosion in Germany after being sent to a distress call at an apartment block. Cops and firefighters were breaking down a door in the high-rise building in the German town of Ratingen when the horror blast happened. APAt least 12 people have been injured in an explosion at an apartment in Germany[/caption] APPolice were called to a building in Ratingen on Thursday afternoon[/caption] APReports claim the explosion may have been deliberate[/caption] Petrol had been spilt in the apartment, which fuelled the blast as officers burst through the door, according to the German publication Bild. The outlet reports the explosion may have been deliberate. A man is believed to have detonated an unidentified object at the high-rise building when police arrived. At least 12 people have been injured and eight are in a critical condition, according to local news outlet ZDF. Gunshots have also been heard coming from the high-rise apartment, according to several witnesses. Video shows police snipers approaching the apartment building in the small town in the North Rhine-Westphalia region of Germany, around 12km northeast of Dusseldorf. Special forces and firefighters have been seen entering the building. Further footage from the ground by a reporter for Bild includes the sound of gunshots. Reports claim a suspect is holed up in the top-floor apartment while smoke can be seen pouring from the windows. Bild has pictured an older man in a dirty grey shirt standing on his balcony while smoke pours out from behind him. Six emergency helicopters are understood to be at the scene. A police spokesman said: “There was an explosion there for reasons that are not yet clear. “Several people are injured, including police officers. “The explosion took place in an apartment in a high-rise building.” Cops are investigating the cause of the blast. It comes after a huge explosion rocked Milan after a van carrying oxygen tanks reportedly ignited. Cops evacuated a nearby nursery and nursing home following the blast which sent black smoke pouring over the Italian city. The blast took place in the Porta Romana area in the southeast of Milan at around midday local time. At least four people have been injured, including one victim who suffered burns to his hand. Italian media reports that the truck carrying the oxygen tanks was parked on a street corner when it exploded, triggering a further eight vehicles to go up in flames, including mopeds. At least one injury has been confirmed after a victim suffered burns to their hand.