Eight hostel staff in Laos are in custody after six tourists died of alleged methanol poisoning last week, the BBC reports.

According to local media, those detained include workers and managers of the hostel in Vang Vieng city where several of the tourists who later died stayed.

It is unclear how many other people became ill and the investigation into the deaths is ongoing.

The owners of the hostel, which is now closed, have denied serving illegal alcohol.

This is not the first time that the police proceeded to detain staff from the hostel. The manager was among several people questioned by police last week.

He earlier told the Associated Press news agency that the 19-year-olds from Australia were the only people staying at the hostel they ransacked after drinking free shots before going out for the night.

The two died days later – after being admitted to a hospital in neighboring Thailand. They were the first deaths suspected to be caused by methanol – a toxic, tasteless and colorless substance commonly added to alcoholic beverages.

Two Danish women and a 57-year-old American who were also staying at the hostel died around the same time.

The two young Danish women – aged 20 and 21 – were found unconscious in their hostel bed on 13 November.

It was the same day the Australians were taken to hospital after going out at a bar in the city the night before, local media reported.

They were taken to a hospital in the capital Vientiane, but died overnight. The medical team said the cause of death was sudden cardiac failure.

Also on November 13, the hostel staff noticed that the American tourist – had not left his room.

When they went to check on him, they found him dead in bed, with several empty drink glasses nearby. There were no bruises or injuries on his body, local media reported.

A 28-year-old lawyer from London also died after she was believed to have ingested methanol while staying in the Vang Vieng area.

The tourist deaths have thrown the popular city into the spotlight and are scaring tourists, especially women, as five of the six who died were female travelers.

Governments including New Zealand, Australia and the United Kingdom have warned their citizens against drinking alcohol in Laos.

Methanol poisoning is most prevalent in Asia, mostly affecting poorer communities and places.

The Australian Broadcasting Corporation (ABC) reported on Tuesday that another Australian, a dual citizen, may also have fallen ill with methanol poisoning.

A New Zealander who fell ill from alleged methanol poisoning in the country has now returned home, authorities have confirmed.