When Danny Wells dropped to his knees after the London Marathon his girlfriend thought he was injured, but he was actually about to propose.

The 24-year-old had carried an engagement ring in his shorts pocket throughout the gruelling 26.2 mile course in a bid to pop the question when Nikita Hallahan was least expecting it.

Mr Wells, from Radlett, said he decided he would pop the question three weeks before the race.

He said: "For the first few miles I was concentrating on just running but near the end I started thinking about the proposal and I knew it was getting closer and closer.

"I was tapping my pocket every mile or so to make sure the ring was still there.

"I did start to worry what would happen if I didn't finish, but that wasn't a problem.

“It was all a bit of a blur but it was perfect, everything I wanted it to be.”

The athlete, who was running his first marathon on Sunday, knew his partner and their families and friends would be at the finish line.

He said when he got to Big Ben he got down at one knee, and at first family thought he was passing out.

Miss Hallahan, 23, who works as a duty manager, said: "Once he had finished the marathon he surprised me by getting down on one knee and proposing to me in front of family, friends and the many people walking by collecting their loved ones from the meeting points.

"I burst into tears and screamed, yelled his name and cried some more.

"I think the word surprise is an understatement, I was completely and utterly in shock. This week I am still catching glimpses of the ring and it reminds me that it all happened.

"It was such a perfect situation and we had family and friends around to witness the wonderful moment and also capture it on camera which is fantastic."

The couple have been together for eight years after meeting at Marlborough School in St Albans.

Mr Wells, a groundsman, was running for the British tinnitus association.

He finished in five hours and 19 minutes and has raised nearly £1,000.

To sponsor Mr Wells, visit: www.justgiving.com/danny-wells.