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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A glorious end to the week, with sunshine which may turn a little hazy later! Temperatures will peak today!
A dry night with incredibly mild temperatures. Setting us up for another lovely day tomorrow!