Stuart Trimby from Cardiff told us how he was on the last mile of the Boston Marathon when he heard two explosions.
Pictured here with his friend Emma Clatworthy Davies before the race, he said he feels "shock and sadness" at the way a positive occasion was ruined by the explosions.
You may find some of the images in the video upsetting.
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Swansea City have signed defender Martin Olsson from Norwich on a two-and-a-half-year deal for an undisclosed fee.
A colder day than yesterday, especially in the east. Remaining cloudy with some patchy light rain and drizzle, mainly over higher ground.
The party groups decide their positions for this afternoon's crucial vote on whether to support the Wales Bill.