Prime Minister Gordon Brown has condemned the Taliban as “cowardly” for using a 13-year-old apparent suicide bomber to spark an explosion which killed a Shropshire Royal Marine.

Damian Davies, who was about to become a father for the second time, was killed alongside two colleagues in the terror blast in Afghanistan.

Tributes poured in for the 27-year-old, of Telford, Shropshire, who was described as the “perfect husband” to his pregnant widow Joanne, who he married only last year, and a doting father to the couple’s son, Matthew.

Marine Davies, who was with the Commando Logistics Regiment, died alongside Kosovo veteran Sgt John Manuel, 38, of Gateshead, Tyne & Wear, and recently-married Cpl Marc Birch, 26, of Kingsthorpe, Northamptonshire, who were both serving with 45 Commando.

The news comes after a fourth man Lance Corporal Steven Fellows, 26, from High Wycombe, died in a separate incident during a patrol earlier the same day when his vehicle bore the brunt of an explosion.

Their deaths bring the number of British military fatalities in Afghanistan since the start of operations in 2001 to 132.

Affectionately known as Damo to his friends, Marine Davies was hailed a hero on a group set up on social networking website Facebook.

Cpl Ben Parks wrote: “In work Damo was the first to volunteer no matter what the task and he would make sure it was seen through to the end, never afraid of getting his hands dirty and not happy unless it was completed perfectly.

“Damo was always talking of his wife and son – he loved and adored them with all his heart, and what a huge heart he had.

“Damo will be remembered as a great friend and a perfect husband and father. He will be greatly missed by all who had met and worked with him.

“Rest in peace Royal.”

Alison Grayson added: “Damo, we have lost such an amazing friend. Love you and will miss you so much.”

Another friend, Charlie Hassall, added: “Damo was a true hero. God bless him and his family.”

The three soldiers were taking part in a routine operation against enemy forces in the south of Sangin on Friday when a 13 year-old Afghan boy approached pushing a wheelbarrow full of explosives which were hidden under papers.

Reports suggest the boy died as a result of the explosion, but it is not yet known if he was a suicide bomber or if the bomb was detonated remotely.

Cpl Birch and Sgt Manuel died at the scene. Marine Davies died later in hospital at Camp Bastion.

Marine Davies’ Squadron Commander Major Marcus Taylor paid tribute to him, saying: “He was always at the forefront of activity and the first to volunteer from his troop no matter how difficult or dangerous the mission.

“A proud husband and father, he will leave a void in many lives that will be impossible to fill.”

His Commanding Officer, Colonel A.T.W Maynard, added: “Marine Davies’s courage was resolute as his tragic death in the front line is testament to.

“His cheerfulness is epitomised by the fact that nobody can remember him without a ready smile.

“At work his style was understated and selfless, and he had a reputation for working hard.

“Nevertheless, although he was a loyal and dedicated Royal Marine, his focus in life was his family - his wife Joanne and son Matthew.

“His extended family in the Commando Logistic Regiment share their loss and their pain, and our thoughts are with them at this time.”