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And the 37-year-old princess's suffering was etched on her face as she and her husband Crown Prince Haakon attended a special church service on Sunday.
It was held at the historic Norderhov Church on the Tri Fjord, near where the massacre on the island of Utoya occurred.
Mette-Marit was visibly distraught as she offered sympathy and condolences to survivors of the attack and victims’ families.
Her children, Marius, Princess Ingrid Alexandra and Prince Sverre Magnus were also in attendance and lit candles in memory of the victims.
Meanwhile, King Harald and Queen Sonja were accompanied by the Norwegian Prime Minister Jens Stoltenberg and their daughter Princess Martha Louise as they attended a service in Oslo cathedral.
Overwhelmed with emotion, the king and queen bowed their heads and wept as Mr Stoltenberg told the gathered mourners they had witnessed a 'national tragedy'.
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