The life of an American man was likely saved by his mobile phone, after it took the full force of a bullet fired in an attack on an Istanbul nightclub, his brother has said.

William Jacob Raak, a business owner from Pennsylvania who goes by the name Jake, was celebrating New Year's Eve in Turkey when he was caught up in the massacre.

Some 180 bullets were sprayed at a 600-strong crowd at the exclusive Reina club – on the shores of the Bosphorus river – leaving 39 people dead.

Footage shows gunman unleash wave of bullets outside Istanbul nightclub

"When he got shot the bullet hit his phone," Jake's brother Michael Raak told NBC10.

"It went from his hip to his knee but the bullet didn’t hit any major arteries".

Doctors told him the mobile likely saved his brother's life, WPVI-TV reported.

Surgeons removed the bullet, and Jake was due to be discharged soon, Michael said.

Jake – who lives in Greenville, Tennessee – and is originally from Chadds Ford, Pennsylvania, was visiting Istanbul with his friends, his brother said.

He was captured on video of the aftermath of the shooting "I was shot in the f****** leg man. These crazy people came in shooting everything."

Later, Jake recalled the attack to NBC News: "Somebody said that there were shots fired and I initially did not believe it until I saw the gunman and he started shooting up the whole place,"

He added that he survived the attack by pretending to be dead after he was shot.

"I just let him shoot me," he said. "You just have to stay as calm as you can [...] I took a bullet."

In pictures: Istanbul nightclub attacked during New Year party Show all 9 1 /9 In pictures: Istanbul nightclub attacked during New Year party In pictures: Istanbul nightclub attacked during New Year party People talk to medics in an ambulance near the scene of an attack in Istanbul on 1 January 2017 AP In pictures: Istanbul nightclub attacked during New Year party People near the scene of an attack in Istanbul on 1 January 2017 AP In pictures: Istanbul nightclub attacked during New Year party Police secure area near an Istanbul nightclub, Turkey, January 1, 2017. Reuters In pictures: Istanbul nightclub attacked during New Year party Ambulances line up on a road leading to a nightclub where a gun attack took place during a New Year party in Istanbul, Turkey Reuters In pictures: Istanbul nightclub attacked during New Year party Turkish special force police officers and ambulances are seen at the site of an armed attack January 1, 2017 in Istanbul Getty In pictures: Istanbul nightclub attacked during New Year party People embrace near the scene of an attack in Istanbul, on New Year's Day AP In pictures: Istanbul nightclub attacked during New Year party Medics carry a wounded person after an attack at a popular nightclub in Istanbul on 1 January AP In pictures: Istanbul nightclub attacked during New Year party Turkish police secure the area at Ortakoy district under Bosphorus Bridge after the attack on Reina nightclub Getty Images In pictures: Istanbul nightclub attacked during New Year party People leave a nightclub in Istanbul after it was attacked on 1 January AP

Jake also said he was "the luckiest person", in the attack that injured 70.

Nearly two-thirds of those killed were foreigners, many from the Middle East.

Isis have since claimed responsibility for the massacre.

Jake is not the first thought to be saved from more serious injury by a mobile phone.