Former US President Bill Clinton has tweeted:
One year later, inspired by so many stories of survival and hope. My thoughts are with Boston today. #BostonStrong
More top news
The actor joined hundreds of mourners at the funeral of the 30-year-old make up artist in the village of Cappawhite, Ireland.
Odense zoo plans to publicly dissect a year-old lion - undeterred by outrage at giraffe who was killed in Copenhagen last year.
The Duke and Duchess of Cambridge met young people who have battled mental health issues on Saturday.