Jez Hughes, a firefighter from Morley, West Yorkshire, had completed the marathon and was walking to the subway with his wife when they heard two explosions.
He had been standing only 100 yards from the finish line with other competitors but walked around the corner to meet his wife.
I had already finished and a few of us had congregated 100 yards past the finish line.
I was waiting for my wife as I had asked her to meet me there but she was in the family area.
Fortunately for me I went round the corner there to meet her.
While we were going to the subway we heard two explosions. I said straight away that sounds like a bomb and then we heard a second one.
We were a couple of blocks out of the way so it did not affect us.
This is my tenth marathon but this is my first time in the USA. I'm watching the aftermath on the TV now, which is a bit surreal to be honest.
My wife is very shook up.
Our condolences go out to those who have lost loved ones.
More top news
Dozens of organisations have filed statements slamming the Zimbabwean president's appointment due to his alleged human rights violations.
Storm Brian will bring strong or very strong winds across southern and western parts of the UK with gales or severe gales in exposed areas.
Omid Saidy, 20, was knifed to death after asking a drug dealer and another man to leave the area, police say.