Papua New Guinea authorities have confirmed that an Air Niugini plane has missed the runway in Micronesia and ended up in the ocean.

Key points: Air Niugini plane landed in the ocean off the island of Weno

Air Niugini plane landed in the ocean off the island of Weno A first responder told ABC there were 36 passengers and 11 crew on board

A first responder told ABC there were 36 passengers and 11 crew on board The plane has previously been involved in an accident last year

The PNG Accident Investigation Commission is preparing a team to travel to the site of the accident off the island of Weno.

Chuuk airport manager Jimmy Emilio told Pacific Daily News the plane crashed into the lagoon about 9:30am local time, ending up 160 metres from the runway.

First responder Dr James Yaingeluo told the ABC 36 passengers and 11 crew were on board, with no casualties.

While Air Niugini originally said they had accounted for all 47, they said on Saturday that one man is still missing.

Air Niugini said in a statement that it was working with local authorities, hospitals and investigators to try to find the man

They did not offer details about his age of nationality.

Map Weno Island is located in the Chuuk lagoon.

Dr Yaingeluo said initially there were nine people taken to hospital, including one who was seriously injured.

"There was a little bit [of] chaos at first because everybody was really panicked and tried to get out of the plane … other than that we were doing as much as we can. Luckily there are no casualties," Mr Yaingeluo said.

"As soon as the plane was in the water the civilians were right there and tried to help, and it made our job easier and much faster so I think we should … always thank the civilians for all the help they did."

Dominic Kaumu, General Manager Commercial at Air Niugini, told the ABC four people were in hospital.

Nine people were taken to Chuuk hospital in Micronesia, with one passenger was seriously injured. ( Facebook: Matthew Colson )

"[The] rest are being put into hotels awaiting a rescue flight from [Port Moresby] which we [will be] sending shortly," he said.

Flight PX073 was coming in from Pohnpei in Micronesia and was scheduled to continue its journey through to Port Moresby, the capital of PNG.

PX073 is serviced by a Boeing 737-800 series aircraft.

The surviving passengers and crew were helped out of the plane by local fishing boats. ( Supplied: Dr James Yaingeluo )

Videos posted to social media show small boats helping people to safety.

The plane is listed on the Aviation Safety Network website as having been involved in an incident at Jacksons International Airport in Port Moresby in May of this year, when the wing of a Lockheed L-100 Hercules aircraft impacted the plane's right winglet, causing "significant damage" to both aircraft.

It is still unclear what caused the crash.

Air Niugini is PNG's leading airline, servicing both national and international destinations.

Chuuk airport is diverting incoming flights to Pohnpei.