A serving soldier was being questioned on suspicion of murder on Tuesday after a woman was stabbed to death.
Ian Lowe from the 1st Battalion the Duke of Lancaster's Regiment is being held in connection with the death of Leanne McNuff in Greater Manchester, sources said.
Police said they were called to Mellor Street in Droylsden at about 7.45pm on Sunday by the ambulance service following reports a woman had been assaulted.
A spokesman for Greater Manchester Police said: "Officers attended and found 24-year-old Leanne McNuff had been seriously injured. She was taken to hospital where she was pronounced dead a short time later."
A post-mortem examination has concluded that she died from multiple stab wounds.
A 24-year-old man was arrested on suspicion of murder and remained in police custody for questioning, police said.
A policeman outside the scene
A spokesman for the Ministry of Defence said: "We can confirm that on March 11, a serving soldier from 1 Lancs was arrested on suspicion of murder."
He added: "The matter is subject to an ongoing civil police investigation and it would be inappropriate to comment further whilst this is ongoing."
It is understood that the soldier was not on leave from Afghanistan.
Detective Inspector Graham Brock, from the Major Incident Team, said: "Our thoughts are with Leanne's family and friends at this time, who are understandably distraught that their loved one has been taken from them in this way.
"We are in the early stages of the investigation and are working to establish the full circumstances of what has happened.
"I would like to reassure residents that we do not believe there is any danger to the wider community, as we believe this is an isolated incident. We would urge anyone who may have seen or heard anything to contact us."
The arrested soldier is from the same unit as Sergeant Nigel Coupe, 33, who died along with five other soldiers last week when a Taliban roadside bomb destroyed their Warrior armoured vehicle in Helmand province, Afghanistan.
Pte Lowe featured in an interview in the Manchester Evening News in February 2008 when he returned from a tour of Iraq to see his son for the first time.
His girlfriend, Miss McNuff, gave birth to Jaden only 10 days after the soldier was sent to Basra, the newspaper reported at the time.
A photograph showed the soldier gleefully holding Jaden aloft, while another captured the couple with their son.
Pte Lowe told the newspaper: "It was wonderful to see him. I was worrying about Jaden and Leanne but my mates knew what I was going through and were very supportive."
It is understood that police are treating the death as a domestic incident.