The parents of a woman who died alongside her fiancee after drinking poisoned limoncellos in Vietnam have revealed they ordered the deadly drink as a Christmas present.

Greta Otteston, 33, and Arno Quinton, 36, were found dead on Boxing Day in Hoi An as a result of methanol poisoning.

Greta had been living in Hoi An with her South African partner, where the couple ran a villa renting rooms to tourists, BBC News reported.

Her parents Paul, 71, and Susan, 70, travelled to Vietnam in November to meet Arno for the first time.

The family ate together at a well-known Italian restaurant called Good Morning Vietnam, which offered them free shots of homemade limoncello after their meal.

Shortly after their visit the couple announced their engagement.

When Paul and Susan arrived home they decided to order a bottle of limoncello from the restaurant to be delivered to their daughter as a Christmas gift for the happy couple.

Just hours after drinking the limoncello, Greta told her parents that she had a terrible hangover and was seeing black spots.

Greta Marie Otteson, 33, and her fiance Els Arno Quinton, 36, were found dead in their villa in Vietnam

Both Greta and Arno died from methanol poisoning from the limoncellos which they received as a Christmas present

Her parents and a friend told her to seek medical help, but she brushed off their suggestions and said she was going to lie down instead.

On Boxing Day, Greta and Arno were found dead in separate rooms of their villa.

Post mortem examinations found the couple died from severe methanol poisoning.

The barman who allegedly made the limoncello was arrested in February and is currently being held without charge.

He was arrested on suspicion of 'violating regulations on food safety' by 'using used 70-degree medical grade alcohol, along with filtered water, lemon peel and white sugar to create two bottles of limoncello'.

If convicted, he could face up to 15 years in prison.

Greta's family say they have not heard any more from the police.

Methanol is a type of alcohol which is toxic and flammable, used as fuel or in cleaning products.

A bartender was arrested over the deadly drink he allegedly supplied to the couple, he has not been charged

Greta's family say they have not heard any more from the police since February

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It is similar to ethanol, which is used for alcoholic drinks but is generally more expensive.

Methanol is more dangerous to humans due to the way it is processed within the body.

Paul described his daughter as a 'marvellous free spirit' saying his daughter studied in Cardiff, Paris and Los Angeles before moving to Vietnam.

He described Arno as quiet but intelligent and said he would have 'loved' to have him as a son-in-law.

The charity Doctors Without Borders have revealed that hundreds of people are poisoned by methanol every year in South East Asia.

Five weeks earlier, six people, including Simone White, 28, a British lawyer, died after drinking methanol-laced shots in a Laos backpacking hotspot ,the landlocked country bordering Vietnam.

Paul and Susan were warned that investigations in Vietnam can be a slow process, with suspects often held for a year before they are charged or released.

They have both Greta and Arno's ashes at their home in Rhandirmwyn, Carmarthenshire. The couple say they cannot put them to rest until they have a 'proper conclusion'

Paul said: 'We can't move on. Susan's asking me every morning when we wake up, "is there any news? Is there any news?" I have to say "no, nothing yet".'

Arno was described by Paul as quiet but intelligent and said he would have 'loved' to have him as a son-in-law

Greta was described as a as a 'marvellous free spirit' by her father

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'Justice for us would be naming the people responsible and prosecuting them.'

The couple also feel let down that the restaurant where they had ordered the limoncello was still open and had not publicly apologised.

'They just carried on as if nothing has happened,' said Paul.

As Greta was their only daughter, the couple are still experiencing the pain that they will never have grandchildren and Arno will never visit Wales.

They said that once the investigation is concluded, they will lay Greta and Arno to rest.

Friends of the pair flooded social media with heartfelt tributes after their death, with one stating: 'Greta loved Arno unconditionally and was his bedrock, giving him the freedom to do what he needed to without a faltering foundation'.

He went on to say: 'There are two distinct things that are so prominent in my thoughts and that is her laugh and how much love they constantly [threw] at each other, regardless of who was around.

'They celebrated each other there and I know they will continue doing that, wherever they are.'

The restaurant where they ordered the limoncello remains open and has not publicly apologised.

Arnold's friend Dayle Visser wrote online: 'Rest in peace my brother. Thank you for always being the fierce friend you were. You saved me many a time.

'You were real and lived life harder than most people could ever dream of. I love you and I will always miss you.'

Another close friend to Mr Quinton had sent him voice message just hours before his tragic death.

The friend - who preferred to not be named - said he had 'sounded super happy and excited about Christmas'.

'I think their plans were just to be together and experience [Christmas] in a new country. It's very tragic'.

We bought the poisoned limoncello that killed our daughter