Boston Mayor Marty Walsh urged people on Twitter to join in a moment of silence to honour those affected by last year's marathon bombings:
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It ends a political standoff that briefly saw Yahya Jammeh and Adama Barrow claiming leadership of this tiny West African nation.
Britain is braced for sub-zero temperatures expected to bring 'harsh frost' through next week.
The historic moment was watched by 500 people in the Church in Wales who cheered after the ceremony.