Families of Holly Bowles and Bianca Jones welcome Laos arrests ...

The bodies of two Melbourne teenagers who died after suspected methanol poisoning in Laos have returned home, as their families urge authorities to continue to pursue those responsible.

After arriving at Melbourne Airport on Tuesday night, the fathers of Bianca Jones and Holly Bowles welcomed news that Laos police had arrested eight men over the deaths of six backpackers, including their daughters.

Bianca Jones and Holly Bowles, both 19, died after drinking tainted cocktails in Laos. (Supplied)

Ms Jones's father, Mark Jones, said the families needed space to grieve.

"We miss our daughters desperately. I was happy to hear there's been some movement over in Laos," he said.

"I would continue to urge our government to continue to pursue whomever. We will make every effort we can to help raise awareness of methanol poisoning."

Earlier on Tuesday, Laos police told the ABC they had detained eight men who were staff and management of the Nana Backpackers hostel, where Ms Jones and Ms Bowles, both 19, were staying when they fell ill.

Ms Jones and Ms Bowles had consumed alcoholic drinks while holidaying in the backpacker party town of Vang Vieng, and later died in separate hospitals in Thailand.

A further four foreign tourists from Denmark, the UK and the US have also died.

It has emerged that another Australian, a dual national, may also have fallen victim to methanol poisoning.

The Department of Foreign Affairs (DFAT) is supporting that person, who is in a stable condition.

On Monday, the New Zealand embassy in Thailand confirmed one of its citizens was suspected to have been poisoned by methanol in Vang Vieng around the same time as the other victims.

They had since returned home after being hospitalised, but the embassy did not provide details of their condition.

A street in the riverside town of Vang Vieng. (ABC News: Mitchell Woolnough )

British woman Lucy Davison also said on social media last week she spent five days in a Vientiane hospital after being poisoned around the same time.

The parents of the two Melbourne girls, along with the Australian government, have been calling for a thorough and transparent investigation into their deaths.

Police in Laos last week forcibly shut down the Nana hostel, where five of the six victims who died were staying.

They questioned staff including the bartender and owner, while the Laos government vowed to bring those responsible to justice.

A DFAT spokesperson on Tuesday night said they were continuing to provide consular assistance to the families of the two Melbourne girls.

"Australian officials in Laos and Thailand are working closely with local authorities. Investigations are underway and we are offering any assistance we can provide," they said.