Six people were killed by a powerful storm that swept through northern and eastern Germany on Thursday, knocking down trees and cranes and causing commuter havoc.

At least four of the victims were killed by trees that crushed their cars in the eastern state of Brandenburg and Mecklenburg-Vorpommern, as well as the cities of Berlin and Hamburg.

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Berlin’s fire brigade declared a state of emergency and issued a warning to residents to stay indoors as storm Xavier ripped its way through the north of the country.

Biggest #sturm I've experienced in 23 years in #Berlin. Police warning people not to walk near trees. pic.twitter.com/xEjSKcbkSZ — Jefferson Chase (@chaseongermany) October 5, 2017

#xavier Orkan better not going for a run in the park today pic.twitter.com/9HMyyLv4NY — Christiane Schmidt (@visionsoftheenv) October 5, 2017

The storm reached category 3, on a 4-point scale. At one point the German Weather Service (DWD) said the storm reached hurricane-strength wind speeds of between 105 and 115 kilometers (65 and 71 miles) per hour.

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Hundreds of commuters were stranded when trains ground to a halt because most railway lines were blocked with fallen trees. Deutsche Bahn canceled long-distance trains to and from Berlin as well as services in Lower Saxony, Schleswig-Holstein and Bremen and commuter trains in Hamburg.

Chaos in #Berlin as #Xavier hits. All transport suspended, trees down all over city. pic.twitter.com/92AIkMwzqf — Lee Hannon (@HannonTV) October 5, 2017

Gewaltige Schäden im S-Bahn Netz. Wir und die @Berliner_Fw arbeiten mit Hochdruck an der Beseitigung der Schäden. pic.twitter.com/xeTV8BL23x — S-Bahn Berlin (@SBahnBerlin) October 5, 2017

Bremen and Hanover airports canceled some international flights as a result of Xavier and bus services were restricted.

The storm is forecast to move eastward toward Poland overnight.