A journalist from German broadcaster Deutsche Welle says Angela Merkel has broken her pelvis in a skiiing accident.
GroKo is short for "grosse Koalition", a grand coaliton of the two large camps from centre-left and centre-right within German politics.
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The violence began after a counter-protester allegedly doused a female rally organiser with pepper spray.
As temperatures climb through the day, the warmest spots are likely to be across western parts of Northern Ireland and western Scotland.
The foreign secretary has criticised internet and social media giants for failing to detect and remove extremist material posted online.