Three Bougainville residents have been rescued after spending 70 days lost at sea amid a horror couple of months in the Solomon Sea off Papua New Guinea.

The two men and one woman, who were travelling from Nissan Island to Buka Island in the Bougainville region, had been missing since July 18.

A passing foreign vessel located Mitchell Tokiapron, Darell Tokiapron and Horen Kapiatuon on Sunday sailing in the expanses of the Pacific Ocean.

It was estimated they had drifted around 4000 kilometres off course from a simple 150-kilometre planned trip before being found.

On the journey between two PNG islands thier boat was unable to safely manoeuvre while losing speed and power.

The 60-horsepower Yamaha engine ran out of fuel, leaving the banana-boat dinghy without any propulsion and at the mercy of the ocean's unpredictable currents.

The Autonomous Bougainville Government worked with the local Maritime Rescue Coordination Centre and Joint Rescue Coordination Centre in orchestrating search and rescue efforts.

The trio were transported to the closest medical centre in Kiribati for treatment.

According to the latest Pacific reports, the extent of the condition of the rescued passengers was unknown.

The national TV broadcaster in Bougainville reported the rescue had brought relief to their families and the Bougainville community, who have spent more than two months waiting for news and fearing the worst.

The incident follows another recent boating incident where eight men, one woman and two children had left Buka for Nissan on a seven-metre vessel early Saturday morning.

Their outboard motor failed, leaving them drifting in the ocean for more than 19 hours.

They were located after the crew of the Indonesian medical ship witnessed repeated flashlight signals after midnight on Sunday.

All 11 people were given food, water, clothing, blankets and medical checks on board before they were returned safely to their families relatively unscathed.

Both incidents came on the back of six males losing their lives, reportedly drowned at sea last month, while travelling between Muliama and Feni islands off the eastern coast of PNG's New Ireland province.

Described as one of the nation's worst maritime tragedies in recent years, one of two boats which collectively carried 26 people capsized in rough seas.

Nine passengers were aboard the vessel before three of them drifted away for six hours and before reaching Tefa Island.

Two of those survivors were the boat operators.

The other six went missing and amid recovery efforts from rescue crews, with their bodies subsequently found days later.

The first of the bodies washed ashore on Djaul Island in New Ireland, more than 250 kilometres away from where the survivors landed.