The girlfriend of a Scots army captain who died during the London Marathon has said his death has left "a devastatingly large hole in our lives".

Captain David Seath, 31, collapsed just three miles short of the finish line from a suspected cardiac arrest on Sunday. He was taken to St Thomas' Hospital but he was pronounced dead shortly afterwards.

Mr Seath, originally from Cowdenbeath, Fife, was a Fire Support Team Commander with the 29 Commando Regiment Royal Artillery.

Before his death Mr Seath raised around £500 for Help for Heroes (H4H) by entering the London Marathon. A fundraising page set up in his memory has already reached almost £90,000. A further £60,000 has now been donated to his personal JustGiving page.

His girlfriend Gaby Schoenenberger, 29, has paid a moving tribute to the war hero after his death and thanked the public for their support.

She said: "I wanted to thank you all for your kind messages and support during this heartbreaking time. I am reading every single one of them and they give so much more comfort than you know.

"I cannot begin to describe the pain that I, his family and friends are feeling right now. It doesn't make sense, and a character like his being taken away so viciously leaves such a devastatingly large hole in our lives.

"I don't know how we are going to fill that hole, get through it or even come to terms with it but your support is so appreciated and like a blanket for us during these dark times. Thank you."

Mr Seath's mother Libby said: "David has achieved more in 31 years than most people do in 70. He lived his life on the edge and to the full.

"He was running to raise money for Help For Heroes, a cause which was very important to him."

His commanding officer, Lieutenant Colonel Jon Cresswell, said: "The regiment was devastated to learn of the tragic loss of Captain Dave Seath during 2016's London Marathon.

"Dave was an outstanding commando officer, a natural leader and a true gentleman. He was my assistant adjutant and so I knew him very well.

"He served on operations in Helmand with 19th Regiment Royal Artillery before joining the Commando Gunners and earning his green beret."

Lt Col Cresswell described Mr Seath as "witty, charming and polished", adding that he had a great career ahead of him.

He had recently been selected to train the future officers of the Afghan National Army later this year in the rank of major.

The commanding officer added: "The thoughts of the regiment are with [his partner] Gabby and Dave's family and friends at this tragic time. We have lost one of the great characters of our regiment and take strength from the memory of his example and leadership."

The soldier's friends are now planning to walk the final three miles to complete the route in his memory.

Bryn and Emma Parry, co-founders of Help For Heroes, said: "David was doing something extraordinary by running the London Marathon to fundraise and support his fellow soldiers who have suffered life-changing injuries and illnesses.

"Help For Heroes sees every fundraiser as one of Team H4H and we are devastated by the news. Our thoughts and prayers are with his family, his regiment and his friends."