A New Zealand Defence Force aerial survey has encountered huge columns of smoke, ash and rocks billowing from an erupting Vanuatu volcano.
The NZDF tasked an Orion aircraft with monitoring the Monaro volcano on Ambae Island to help Vanuatu's National Disaster Management Office determine if a large eruption was imminent.
"We are pleased that we are able to help Vanuatu authorities with our Orion and our highly skilled crew," group captain Nick Olney said.
"The NZDF always stands ready to support our Pacific neighbours, especially in times like this."
The NZDF has conducted aerial surveys of volcanoes in Vanuatu, the Solomon Islands, and Tonga in recent years, in response to requests from these countries.
Yesterday's aerial survey, which included the Ambrym and Lopevi volcanoes, had been planned before Monaro's recent activity intensified.
Vanuatu authorities raised the official alert level recently to four, as Monaro's eruption intensified.
Alert levels range from 0 to 5, with level 5 indicating a large-scale eruption.
About 10,000 people live on Ambae Island, which has Monaro, one of the most active volcanoes in the world. Monaro last erupted in 2005, prompting the relocation of about 5000 people across the 400 sq km island.
The NZDF deployed about 350 personnel, amphibious sealift vessel HMNZS Canterbury and three aircraft to support disaster relief efforts in Vanuatu following the devastation caused by Tropical Cyclone Pam in 2015.