The parents of a young British officer killed in a roadside bomb blast in Iraq paid tribute today to their "beautiful, talented and loving son".

Lieutenant Tom Mildinhall, 26, whose father is a retired Army officer, died in the attack in Basra on Sunday alongside Lance Corporal Paul Farrelly, 27, a married man with three children.

Lt Mildinhall’s parents, from Battersea, south London, said: "Our world is in pieces and our country has again lost one of its best.

"This is an ordeal I would not wish any mother and father to endure. We have lost a beautiful, talented and loving son for ever."

Both men were serving with the Queen’s Dragoon Guards, also known as the Welsh Guards, based in Osnabruck, Germany, when their Land Rover was struck by a roadside bomb.

Lieutenant Colonel Anthony Pittman, their commanding officer, described Lt Mildinhall as a truly promising officer and said L/Cpl Farrelly was an outstanding soldier and natural leader marked out for early promotion.

Their deaths marked a further deterioration in the security situation in Basra, which Des Browne, the Defence Secretary, acknowledged today was a major concern. Mr Browne reiterated that Britain would not withdraw before it had handed over security to an effective Iraqi force.

Tributes were also being paid to two British journalists killed in a bomb attack in the centre of Baghdad yesterday.

Paul Douglas, 48, and James Brolan, 42, worked as cameraman and sound technician with Kimberly Dozier, a correspondent for American network CBS News.

They had gone out to film a Memorial Day broadcast but for some reason stopped at Tahrir Square on their way back to base. A makeshift bomb in a parked car exploded.

Mr Brolan, a father of two from Tufnell Park, London, was described as "the best dad, the best husband and the best mate to be with in a tight spot out in the field".

Ms Dozier, 39, was today in intensive care after being flown to Ramstein Air Base in Germany. She was hit by shrapnel in the stomach and head. Her condition remains critical.

At a media briefing, Colonel Bryan Gamble said that Ms Dozier was responsive during the flight, opening her eyes and moving her toes, but that it was too soon to speculate on her recovery

"She was critically wounded ... but right now she is doing as well as can be expected," he said.

The bloodshed which led to the loss of at least 50 other lives in Iraq yesterday continued today as insurgents fired mortar bombs at the interior ministry headquarters in Baghdad. Two female civil servants were killed when the rocket exploded into the third floor.

Later, a car bomb killed at least four people and wounded 27 in the southern city of Hillah. Another car bombing in Baghdad killed 22 Iraqis.

Meanwhile, arguments over the appointment of ministers to the sensitive defence and interior ministries posts continued. The formation of a functioning national unity government is seen as critical to the fight against the insurgency but has eluded politicians for six months.

Prime Minister Nuri al-Maliki said that he would personally appoint ministers to the posts by the end of the week if no agreement could be reached.

The human cost of the killing was being felt again in Britain, where the deaths of the two officers brought to 11 the number of British soldiers killed this month - the highest toll since the invasion in 2003.

Lieutenant Mildinhall, 26, was educated at Monkton Coombe in Dorset, and studied computer sciences at Durham University before completing his officer training at the Royal Military Academy, Sandhurst, in April 2004.

He was first deployed to Iraq in September 2004 and assisted in training the Iraqi Border Police. Officers said that he took to this difficult task with enthusiasm and diligence.

He returned to Iraq for his second tour a month ago. A keen rower and skier, colleagues said that they would miss his dry sense of humour.

Lt Col Pittman, his Commanding Officer, said: "He was intelligent, determined and utterly loyal to both his own command and his superiors. He led by example and his soldiers responded positively, safe in the knowledge he had their best interests at heart.

"It was typical of his command style to insist he physically led the more dangerous patrols, as he was doing last night when his troop came under attack and he suffered a fatal injury."

L/Cpl Farrelly, known as Fas, 28, from Runcorn, near Liverpool, joined the Army in March 2002. He was judged top recruit during his term at the Army Training Regiment in Winchester and was on his third tour of Iraq.

Officers said that the football-loving family man was devoted to his wife and three young children.

Lt Col Pittman, said: "He was knowledgeable, quick-thinking and tough. He stood out amongst his peers as a natural leader; level-headed and utterly dependable.

"He embodied much of what is best about soldiers in the British Army: selfless, determined, humorous and steadfast in the face of adversity. Always a committed family man, Paul spoke often and fondly of his wife Natalie, and their three children, Reece, Morgan and Brooke."

Zalmay Khalizad, the US Ambassador to Iraq, said he was "shocked and saddened" by the journalists’ deaths.

Douglas, from Wootton, Bedfordshire, was a veteran cameraman, whose colleagues loved him for his soft-spoken and calm demeanour. In Baghdad, his team affectionately called him "blast wall" because of his big size.

He had worked for CBS in danger zones that included Afghanistan, Pakistan, Rwanda and Bosnia. He leaves a wife, Linda, daughters Kelly, 29, and Joanne, 26, and three grandchildren.

Mr Khalizad said: "These brave journalists risked their lives to tell the world the story of a courageous people and a proud nation," he said.

"The terrorists who committed this evil crime have shown themselves for who they are. They do not want the world to see the truth of what is happening in Iraq, where a determined people are fighting for freedom and liberty. That story must and will be told."

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