A British soldier killed by an explosion on New Year’s Day in southern Afghanistan has been named by the Ministry of Defence.

Serjeant Christopher John Reed, a Territorial Army soldier with the 6th Battalion The Rifles, was on a routine patrol in Garmsir district, Helmand province, when he died on Thursday.

The 25-year-old’s vehicle was involved in an explosion and he died at the scene. It emerged yesterday that he got engaged on the day he left for Afghanistan.

The MoD said he and his fiancee Heather planned to have their wedding when he returned.

His commanding officer, Lieutenant Colonel Tom Mereweather, paid tribute to a “talented, committed non-commissioned officer”, and said the death was a “hammer blow” to the battalion.

Speaking from the unit’s headquarters at Wyvern Barracks in Exeter, Devon, he said: “He was undoubtedly one of my very best section commanders. Calm, modest, easy-going, but with a sense of purpose and obvious steel, he will be greatly missed.”

Sjt Reed, from Plymouth, worked for Babcock Marine at Devonport Dockyard, where he built luxury yachts.

In a statement his family, parents Brian and Joy Reed and brother Andrew, said he believed he was making a difference.

They said: “He touched the hearts of all he came into contact with. Christopher will be sadly missed. We are very proud of what he achieved.”

Sjt Reed is the 138th British serviceman to die since the start of operations in October 2001.

Commander Paula Rowe, spokeswoman for Task Force Helmand, said: “It is deeply saddening to confirm the loss of a British soldier who died while helping to provide security in Southern Helmand.

"His family, friends and all those who knew and worked with him will mourn his loss — our heartfelt sympathies go to them all at this terrible time.”

A spokesman for the MoD said Sjt Reed always “made the best impressions on everyone he met”.

He said during the deployment he led an evacuation of casualties to get them away from a fire fight.

The spokesman said: “His team commander and three Afghan National Army soldiers were injured by shrapnel from a rocket propelled grenade blast.

“Without pause, Chris took control of the situation, overseeing the evacuation of the casualties and then continuing with his patrol.”

Royal Navy Captain Mark Windsor, spokesman for International Security Assistance Force (Isaf), which includes British forces, said: “We are saddened by this brave soldier’s death, and our deepest sympathies go to his family and loved ones.

“This dedicated professional risked his life to help bring security to the people of Afghanistan. Isaf will continue to fight for the cause for which he gave his life.”

The death is the first British loss in Afghanistan in 2009 and follows that of Royal Marine Corporal Liam Elms who was killed on New Year’s Eve.