Ranger Cupples was on patrol in Sangin, Helmand province
A British Army soldier killed in an explosion in Afghanistan on Thursday has been named as Ranger Justin James Cupples, the Ministry of Defence said.
Ranger Cupples, 29, from 1st Battalion, the Royal Irish Regiment, was killed in an explosion while on a routine foot patrol in southern Afghanistan.
An MoD spokesman described him as "tough, committed and dedicated".
Next of kin have been informed. The number of soldiers killed on operations in Afghanistan since 2001 is now 117.
'Strong and determined'
The Ministry of Defence said the explosion, near Sangin district centre early on Thursday, was believed to have been from an improvised explosive device.
The blast left Ranger Cupples unconscious and despite immediate first aid he died 15 minutes later, the MoD added.
Lt Col Ed Freely, commanding officer of 1st Battalion The Royal Irish Regiment paid tribute to Ranger Cupples.
He said: "Justin Cupples was a character. He stood out as such. He was loyal, strong and determined; a very good soldier."
Ranger Ryan Cardwell, one of Ranger Cupple's friends described him as "a breath of fresh air".
He said: "I will especially miss the cups of tea we went for regularly each afternoon to chat. I will also miss having someone to talk to and share my problems with.
"Ranger Cupples was a true good friend and I will miss you rest in peace mate and God bless".
Brig Gen Richard Blanchette, International Security Assistance Force spokesman, offered his condolences to relatives.
He said: "This soldier died honourably, helping bring security to Afghanistan."
'Debt of gratitude'
Ranger Cupples was born in the US to Irish parents and served with the US Navy during Operation Iraqi Freedom.
His family moved from Miami to the Irish Republic, before he joined the British Army and began training in February 2007.
Northern Ireland politicians have extended their sympathies to the soldier's family and friends.
First Minister Peter Robinson said he was shocked and saddened by the death.
"We owe a great debt of gratitude to him and the young people who are fighting to build peace and stability in Afghanistan and protect us from the threat of international terrorism.
"The people of Northern Ireland will be deeply saddened to hear of his death and I would like to take this opportunity to extend my sympathy to his family and his colleagues who continue to fight in Afghanistan."
Northern Ireland Secretary Shaun Woodward said his thoughts were with the soldier's family and his regiment.