SAS sniper Danny Nightingale, who was jailed for illegally possessing a pistol and ammunition, today thanked "the world for being so kind" as he was freed after winning an appeal.

Sergeant Danny Nightingale was sentenced to 18 months military detention earlier this month by a judge sitting in a military court.

He admitted illegally possessing a Glock 9mm pistol and more than 300 rounds of ammunition at a court martial.

Three judges - Lord Chief Justice Lord Judge, Mr Justice Fulford and Mr Justice Bean - heard legal argument at a hearing in the Court Martial Appeal Court in London.

Appeal judges said Sgt Nightingale's sentence would be cut from 18 months to 12 months and suspended.

They said he could be released immediately.

Leaving court he thanked his wife and family and friends and legal team.

"I think they've been amazingly courageous, I think they have been very dignified in what they've done and I am thankful," he said.

"Thank you to the world for being so kind."

Sgt Nightingale's wife Sally, 38, wept at the verdict.

She was lost for words but nodded when asked if she was "thrilled."

She later added: "I didn't dare to dream that this would be the outcome but it's great."

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• Sergeant Danny Nightingale case

  Sargeant Danny Nightingale (centre), his wife Sally Nightingale and father Humphrey (left), outside the Royal Courts of Justice, London, as the SAS sniper walked from the Court of Appeal after having had his sentence for possessing a pistol suspended.

• Sergeant Danny Nightingale case

  Sargeant Danny Nightingale (centre), his wife Sally Nightingale and father Humphrey (left), outside the Royal Courts of Justice, London, as the SAS sniper walked from the Court of Appeal after having had his sentence for possessing a pistol suspended. PRESS ASSOCIATION Photo. Picture date: Thursday November 29, 2012. See PA story COURTS Nightingale. Photo credit should read: Sean Dempsey/PA Wire

• Sergeant Danny Nightingale case

  Sargeant Danny Nightingale and his wife Sally Nightingale, outside the Royal Courts of Justice, London, as the SAS sniper walked from the Court of Appeal after having had his sentence for possessing a pistol suspended. PRESS ASSOCIATION Photo. Picture date: Thursday November 29, 2012. See PA story COURTS Nightingale. Photo credit should read: Sean Dempsey/PA Wire

• Sergeant Danny Nightingale case

  Sargeant Danny Nightingale (centre), his wife Sally Nightingale and father Humphrey (left), outside the Royal Courts of Justice, London, as the SAS sniper walked from the Court of Appeal after having had his sentence for possessing a pistol suspended.

• Sergeant Danny Nightingale case

  Sargeant Danny Nightingale and his wife Sally Nightingale, outside the Royal Courts of Justice, London, as the SAS sniper walked from the Court of Appeal after having had his sentence for possessing a pistol suspended. PRESS ASSOCIATION Photo. Picture date: Thursday November 29, 2012. See PA story COURTS Nightingale. Photo credit should read: Sean Dempsey/PA Wire

• Sergeant Danny Nightingale case

  Sargeant Danny Nightingale and his wife Sally Nightingale, outside the Royal Courts of Justice, London, as the SAS sniper walked from the Court of Appeal after having had his sentence for possessing a pistol suspended.

• Sergeant Danny Nightingale case

  Sargeant Danny Nightingale and his wife Sally Nightingale, outside the Royal Courts of Justice, London, as the SAS sniper walked from the Court of Appeal after having had his sentence for possessing a pistol suspended.

• Sergeant Danny Nightingale case

  Sargeant Danny Nightingale (centre), his wife Sally Nightingale and father Humphrey (left), outside the Royal Courts of Justice, London, as the SAS sniper walked from the Court of Appeal after having had his sentence for possessing a pistol suspended.

• Sergeant Danny Nightingale case

  Sally Nightingale outside the Court of Appeal in London, where she is lodging an appeal for her husband Sergeant Danny Nightingale who was sentenced to 18 months in military detention after after admitting possessing a prohibited firearm and ammunition.

• Sergeant Danny Nightingale case

  File photo dated 21/11/12 of Sally Nightingale outside the Court of Appeal in London, as her husband Danny Nightingale, an SAS sniper jailed for illegally possessing a pistol and ammunition is today hoping to get an 18-month sentence quashed.

• Sergeant Danny Nightingale case

  Sally Nightingale outside the Court of Appeal in London, where she is lodging an appeal for her husband Sergeant Danny Nightingale who was sentenced to 18 months in military detention after after admitting possessing a prohibited firearm and ammunition.

• Sergeant Danny Nightingale case

  Humphrey Nightingale (Danny's father) outside the Court of Appeal in London, where he is lodging an appeal for Sergeant Danny Nightingale who was sentenced to 18 months in military detention after after admitting possessing a prohibited firearm and ammunition.

• Sergeant Danny Nightingale case

  Sally Nightingale outside the Court of Appeal in London, where she is lodging an appeal for her husband Sergeant Danny Nightingale who was sentenced to 18 months in military detention after after admitting possessing a prohibited firearm and ammunition.

• Sergeant Danny Nightingale case

  Humphrey Nightingale (Danny's father) and Sally Nightingale outside the Court of Appeal in London, where they are lodging an appeal for Sergeant Danny Nightingale who was sentenced to 18 months in military detention after after admitting possessing a prohibited firearm and ammunition.

• Sergeant Danny Nightingale case

  Sally Nightingale outside the Court of Appeal in London, where she is lodging an appeal for her husband Sergeant Danny Nightingale who was sentenced to 18 months in military detention after after admitting possessing a prohibited firearm and ammunition.

• Sergeant Danny Nightingale case

  Sally Nightingale and her father-in-law Humphrey Nightingale stand outside the Military Corrective Training Centre (MCTC) in Colchester, Essex, before seeing Sergeant Danny Nightingale, sentenced to 18 months military detention for possession of an illegal weapon by a court martial.

• Sergeant Danny Nightingale case

  Sally Nightingale stands outside the Military Corrective Training Centre (MCTC) in Colchester, Essex, before seeing her husband Sergeant Danny Nightingale, sentenced to 18 months military detention for possession of an illegal weapon by a court martial.

• Sergeant Danny Nightingale case

  Sally Nightingale stands outside the Military Corrective Training Centre (MCTC) in Colchester, Essex, before seeing her husband Sergeant Danny Nightingale, sentenced to 18 months military detention for possession of an illegal weapon by a court martial.

• Sergeant Danny Nightingale case

  The sign outside the main gate of the Military Corrective Training Centre (MCTC) in Colchester, Essex, as Sally Nightingale prepares to see her husband Sergeant Danny Nightingale, sentenced to 18 months military detention for possession of an illegal weapon by a court martial.

• Sergeant Danny Nightingale case

  Sally Nightingale stands outside the Military Corrective Training Centre (MCTC) in Colchester, Essex, before seeing her husband Sergeant Danny Nightingale, sentenced to 18 months military detention for possession of an illegal weapon by a court martial.

• Sergeant Danny Nightingale case

  Sally Nightingale stands outside the Military Corrective Training Centre (MCTC) in Colchester, Essex, before seeing her husband Sergeant Danny Nightingale, sentenced to 18 months military detention for possession of an illegal weapon by a court martial.