Aerial reconnaissance images have revealed shocking destruction on one of Tonga's islands caused by last month's volcanic eruption and tsunami. 

Most structures on Tonga's Atata Island appear to have been wiped out completely – however, a blue and white church remained remarkably intact. 

Australian Defence Force personnel conducting the reconnaissance were surprised to see so many people – including children – living on the island amid the devastation. 

A blue and white church can be seen miraculously intact among the rubble of other completely destroyed buildings. Photo / ADF 

To help avoid furthering the spread of Covid-19 in Tonga, relief operations by the ADF are being conducted with no face-to-face contact with the Tongan community. 

"We have discovered more people on the islands than expected," Major Richard Bremner said. 

"That's of interest to both the government of Tonga and to us, particularly when applying Covid-safe measures to relief operations. 

"We may need to determine how we can work with the government of Tonga to support the movement of those people if we are requested to conduct tasks on those islands." 

The country entered a two-day lockdown on Wednesday night, after recording two new community cases of the virus. 

Children are among those still living on the island amid the devastation. Photo / ADF 

Prior to the tsunami, Atata Island had an estimated population of a little over 100 and its main feature was the Royal Sunset Island Resort. 

According to the organiser of a fundraiser to assist with the island's recovery, people are not yet permitted to return there due to safety concerns. 

"The government is still not sure if the village will be rebuilt and there are discussions that all Atata villagers could be reallocated on the mainland. This has been very traumatic, as it is their home, where ancestors are buried," fundraiser organiser Bruno Dubois said. 

"Obviously for the resort, not much is left standing, except some parts of the main buildings, but there is no way the resort can be rebuilt, as so much land has been swept away." 

Prior to the tsunami, Atata Island had an estimated population of a little over 100 and its main feature was the Royal Sunset Island Resort. Photo / ADF 

The Tongan government has stepped up contact tracing measures in order to ring-fence community transmission of Covid-19. 

Lockdown rules in Tonga will require everyone to remain at home, to practice social distancing, and to wear face masks in public. Essential workers are exempted from restrictions of movement, such as Red Cross and aid distribution personnel, who would be allowed to operate freely. 

According to Tonga's Ministry of Health, more than 83 per cent of the eligible population (over the age of 12) have been fully vaccinated. Exactly 73,938 people (over the age of 12) having been vaccinated at least once, representing 96 per cent of those eligible. 

Donate to Tongan relief effort HERE 

- By Duncan Murray, news.com.au

- Additional reporting, RNZ