A British citizen has been killed in Ukraine and another is missing, the UK’s foreign ministry said on Thursday, both reportedly involved in fighting with Russian forces there amid Moscow’s brutal invasion. The dead man was a military veteran named Scott Sibley, British media reported, with former comrades paying tribute to him although his identity was not officially confirmed. His death is believed to be the first of a Briton fighting in the conflict. He was reportedly 36 years old. “We can confirm that a British national has been killed in Ukraine and [we] are supporting their family,” a Fo…