• Tonga tsunami alert after Hunga Tonga-Hunga Haʻapai erupts
• Fiji and American Samoa issued with tsunami alerts
• Tongan fleeing the waters calls on people to 'pray' for her family
• Moment of huge eruption caught by satellite imagery
• Marine warnings also issued for North Island, Chatham Islands, Fiji and American Samoa
Large waves are washing ashore in Tonga after another violent volcanic eruption hit the island nation - and Government officials issued a second tsunami warning in two days.
Video footage shows waves washing through homes, properties and a church.
The tsunami alert follows yesterday's eruption of Hunga Tonga-Hunga Haʻapai, an underwater volcano, sending ash, steam and gas up to 17km into the air.
Volcanic ash is currently raining down on Nuku'alofa, Tonga's capital.
The police and local authorities have advised for all residents to move to higher ground.
There are reports of sirens ringing across Nukualofa and police are asking people to move to higher ground.
There are also reports on social media of the explosion being heard in Fiji, about 800 kilometres away - and as far away as Samoa, about 880km distant.
The Tonga Meteorological Services posted to Facebook noting a warning is in place for the entire island.
Locals have been posting online, including one who wrote: "A volcanic explosion just erupted and people have evacuated to higher ground now from possible tsunami waves also ash shards are falling and now the ash clouds are covering the island of Tongatapu.
"We live in Kolomotu'a near the ocean so we have left already and we are in our cars heading out but traffic on every road. Please pray for us as a family and safety."
A Twitter user identified as Dr Faka'iloatonga Taumoefolau posted video showing waves crashing ashore.
"Can literally hear the volcano eruption, sounds pretty violent," he wrote, adding in a later post: "Raining ash and tiny pebbles, darkness blanketing the sky."
RNZ Pacific's Finau Fonua says it is dark in Tonga, ash is falling and people can see lightning in the ash clouds.
Tonga's King evacuated
Island Business is reporting that Tonga's King Tupou VI has been evacuated from the Royal Palace after a tsunami flooded Nuku'alofa today.
A convoy of police and troops rushed the King to a villa at Mata Ki Eua as residents headed for higher ground.
Waves generated by the volcano inundated Nuku'alofa, flooding the Palace grounds, waterfront and the main street.
Warning for Pacific Islands and NZ
A tsunami alert has been issued for Fiji and American Samoa and Samoa. Residents of low-lying areas were urged to move to higher ground.
New Zealand's National Emergency Management Agency sent a National Advisory alert to notify of tsunami activity.
"We expect New Zealand coastal areas on the north and east coast of the North Island and the Chatham Islands to experience strong and unusual currents and unpredictable surges at the shore," it tweeted.
There have been multiple reports on New Zealand social media pages of loud booms being heard and houses shaking on Saturday evening.
The booms have been reported all over the country from Tauranga to Invercargill.
MetService says the 'booms' are a surge in the air pressure. Some people around the country have also heard a rumble probably associated with the eruption.
Reports in Fiji says tsunami waves have reached parts of Vanualevu in Fiji.
The Fiji Meteorological Service has issued an advisory - saying there's a risk of abnormal wave heights due to tsunami generated waves from Tonga.
The Fijian Secretary of Health, James Fong, says he heard the sound of a thunderclap all the way over in Fiji.
Dr Fong says the internet connection in the outer islands is poor but he says he is expecting a briefing from Tongan authorities.
Anthony Browne is in Fiji and told the Herald the eruption is still being heard and felt as far away as Nadi, Fiji.
"For the last hour there have been continuous explosive sounds with continuous rumbling, windows rattling and doors rattling."
Samoa and American Samoa
In Samoa, more than 100 families have reportedly been evacuated from villages on the southern side of the big island of Savaii after wave surges hit homes at Vailoa, Palauli, about 6pm.
Locals told Samoa's Eyespy Radio that "huge waves" struck the coastline and caused damage to houses in the villages of Palauli and Satupaitea.
Villagers reported windows "rattling" shortly beforehand and was what initially thought to be thunderstorms were remnants from the volcano eruption in Tonga.
The Samoa Meteorology division has said no evacuation is necessary, but it is understood many villagers have taken it upon themselves to head to higher ground.
"For the safety of the public, it is advised to not go near beaches or coastal areas," an alert said.
People on the other side of Savaii are also preparing for a late night evacuation.
A local told the Herald there were no warnings being broadcast on television, but people living on the coast are preparing to leave.
"Sirens and bells are going off and we're packing just in case."
Reuters is reporting that tsunami waves measuring 60cm in height were observed by sea-level gauges at the capital of the US territory of American Samoa following volcanic activity in Tonga, quoting the US-based Pacific tsunami warning centre.
The tsunami threat continues and sea level fluctuations and strong ocean currents pose hazards along beaches in harbours, the tsunami monitor said in a statement to Reuters.
Volcano declared dormant on January 11
The Hunga Tonga-Hunga Haʻapai volcano is located about 30km south-east of Fonuafo'ou island in Tonga. It had been active from December 20, 2021, but was declared dormant on January 11.
On Friday, several Tongan geologists went to observe the Hunga Tonga-Hunga Haʻapai volcano.
Taaniela Kula, Deputy Secretary, Ministry of Lands & Natural Resources – who was in charge of the group – told local media outlet Matangi Tonga: "Yesterday there were massive explosives, thundering lightning within two miles away, we observed and recorded.
"Big day yesterday indeed!. It was great getting out there during the volcano's peak hours. It's a geologist's dream to see actual geological events in process."
The ongoing plumes of debris from the volcano earlier saw a halt of flights in Tonga.
As of yesterday, the maximum tsunami wave had been recorded in Nuku'alofa tide gauge at 12:30pm and was about 30cm above sea level.