The number of people believed to have been on board the Tongan ferry Princess Ashika when it sank on Wednesday has risen to 141.

Maritime New Zealand, who are involved in the search for survivors, this morning had the figure at 120.

Spokesman Ross Henderson said it had been difficult getting a complete and accurate passenger list.

With 54 people rescued and two bodies recovered so far, there remain 85 unaccounted for, believed drowned.

The Princess Ashika was travelling from Tongan capital Nuku’alofa to Ha’afeva, in the Nomuka Islands group, when it sank moments after issuing a mayday call. It has been located in 35m of water, about 86km northeast of the capital.

Mr Henderson said an airforce Orion and several boats were still searching with the plane expected to stay out until about 1pm (NZ Time).

“Depending on if we find anything, we’ll reassess if there is any more that can be done.

“Obviously the more time that passes, the less the chances.”

A New Zealand Navy team of 12 divers and three specialist staff was despatched last night to join an Australian team in searching for bodies today.

Filo Akauola, editor of the newspaper Talaki, told Radio New Zealand a second vessel, owned by a Tongan MP, was sailing about 25 minutes behind the Princes Ashika on Wednesday night and those on board helped rescue the ferry passengers from the water.

He said the area was known for rogue waves.

In the aftermath questions have arisen as to how the aging ferry had been allowed to operate.

Veteran democracy MP ‘Akilisi Pohiva said people were “extremely angry” as they had tried to stop the monarchy-ruled government from buying the ancient boat.

Its refusal to listen, and the lack of proper government accountability, was triggering increasing tensions “not unlike what we’ve seen here before”.

People were gathering outside the offices of the government-owned Shipping Company of Polynesia, which bought the boat from Fiji two months ago as a stop gap measure before a new vessel was launched in 2011.

“People are extremely angry, everybody knew this ship was going to sink,” Mr Pohiva said.

“It was an old ship, it was only good for scrap.

“I have been to the marine department and spoken to their people, and they say it was not licensed and it should not have been operating.”

Leading Tongan journalist Pesi Fonua said locals had a “bad feeling” about the boat.

They had not wanted to travel on it but had no choice as air travel was too expensive.

Adding to the Tongan people’s fury was the news their monarch, King Tupou V, had left the country on an extended Scottish holiday despite being aware the tragedy had occurred.

Brian Heagney, who runs a dive shop in Nuku’alofa, told New said “the mood in the entire kingdom is one of anger”.

“Particularly at the shipping company because (people think) the boat is not up to standard and they sailed it anyway,” he said.

“Very large crowds have camped outside the offices basically baying for blood.”

Information was being passed on “painfully slow”, and many people were still not aware whether their family members were alive or dead.

It is hoped the tragedy, coupled with the king’s untimely departure and the prime minister’s absence for the Pacific Islands Forum in Cairns, does not spark another riot such as the one seen in November 2006.

Most of Nuku’alofa’s town centre was looted and razed by demonstrators to protest the royal family’s stranglehold on Tonga’s governance and economy.

A repeat would be a major setback for the country, which has made several steps towards a more open democratic system in the past year and hopes to hold its first citizen-focused elections in 2010.