But they have now been charged with using excessive force causing death

The officers said they were forced to restrain her after she became violent

She was supposed to be traveling to Chicago but missed her flight - and ended up arguing with officers at Ataturk Airport, Istanbul

Tracey Lynn Brown, 48, died after being restrained by police officers in Turkey

Twelve police officers are facing a possible prison sentence for their alleged involvement in the death of an American tourist at a Turkish airport more than two years ago.

Tracey Lynn Brown died in April 2013, almost two weeks after she was supposed to have left Ataturk Airport in Turkey for Chicago.

For reasons unknown, she never caught her flight back to the States.

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Calm: The CCTV footage begins with Tracey Lynn Brown walking to passport control, where she apparently gets into an argument with police officers which would end with her dying in intensive care 13 days later

Instead, she ended up in an argument with the airport's police officers, who eventually forcibly restrained her for almost 20 minutes, before getting a doctor to sedate her.

Shortly afterwards, they realized Ms Brown no longer had a pulse and despite their best efforts, she never regained consciousness.

CCTV footage of the incident shows Ms Brown face down and gasping for breath underneath the weight of their restraint.

Other images show them pulling her lifeless body around before beginning chest compressions.

The 12 officers are now facing charges of 'using of excessive force leading to death', which, if found guilty, carries a sentence of between 12 and 16 years.

Meanwhile, the doctor who oversaw the sedation is facing the possibility of two to six years behind bars, accused of negligence.

Ms Brown first arrived at the airport on the morning of April 4, having flown in from Tashkent, Uzbekistan.

She was supposed to be in the airport for 13 hours, and was catching a connecting flight that evening.

But it appears she missed her flight, and is seen on CCTV at about 9.50pm approaching what seems to be passport control.

She is then taken to a room, where she was is seen to start arguing.

'Aggressive': The police claim Ms Brown became violent and they were forced to restrain her

In a police statement, they claimed she asked for her daughter, and refused to talk to anyone else.

It is unclear if her daughter was with her at the time.

By 10.01pm, she wasn't visible on camera anymore, and is next seen on CCTV at 4am, six hours later.

This footage shows her trying to jump over the counter, attack a computer and throw papers.

The 48 year old also had scissors in her hand, and used them to injure one of the officers hands

Ms Brown is then handcuffed to a chair, but manages to escape in less than a minute.

It is now that six officers tackle her to the ground and handcuff her: she is held in the position for 17 minutes before the doctor - named as 'Mehsut O' - is called.

He tells other medics to give her a sedative, which was administered.

The group of medics then wait four minutes before they all leave the room.

The officers let go of her after she had been sedated - but the 48 year old didn't have a pulse

It is only then that the police officer releases his knee from Ms Brown's back - and then makes the horrifying discovery that she doesn't have a pulse.

It takes the doctor another six minutes to return.

He then tries to resuscitate her for seven minutes, before she is sent to the Bakirkoy Dr Sadi Konuk Education & Research Hospital, which is 10 minutes away.

She was later moved between hospitals, before dying in intensive care on April 18.

An autopsy revealed her death had been caused by continuously applied pressure to the neck and chest.

The police officers deny they used excessive force, and have said she acted aggressively.