At least eight people have died and more than a dozen others remain missing after a passenger ferry capsized off the coast of northern Cyprus, according to the head of the Turkish administration there.

Unal Ustel, prime minister of the self-proclaimed Turkish republic on the island, said the vessel had been carrying 259 passengers and eight crew members when it began taking on water after departing the coastal town of Kyrenia.

The ship's captain and seven crew members have been detained as part of an investigation into "how this tragedy occurred", Ustel wrote on social media.

A search and rescue operation to locate passengers still unaccounted for is under way, with Turkish authorities participating.

The privately owned ferry left the popular holiday resort of Kyrenia at approximately 12:30 local time (09:30 GMT). Ustel said the boat had been scheduled to travel to Turkey on Saturday but was delayed due to poor weather conditions.

He told a Turkish media outlet that the boat was struck by two waves before it capsized. While the captain was attempting to recover from the first wave, a second wave hit and the vessel began taking on water.

Helicopters and coastguard boats have been dispatched to the scene, while ambulances have been stationed on the beach ready to receive rescued passengers.

Ustel wrote on social media that the "priority right now is human life", adding that security forces, rescue teams and health officials were all on the scene. He added that the disaster would be thoroughly investigated and "even the slightest negligence will be uncovered".

"No one will be spared, regardless of who they are, who is found to be at fault or responsible," Ustel said.

Erhan Arikli, the transport minister of the self-declared Turkish Republic of Northern Cyprus (TRNC), told local media that 100 passengers had been brought to shore. On Sunday evening, he confirmed that the ship had completely sunk.

Turkey's President Recep Tayyip Erdogan sent his condolences to Turkish Cypriots and said efforts to reach those still missing "continue uninterrupted".

"Immediately after the accident, we launched extensive search-and-rescue operations in co-operation with the authorities of the Turkish Republic of Northern Cyprus," he said at a military ceremony on Sunday.

A local resident, Mustafa Koc, said he saved around 65 people using his own boat after the vessel capsized. He said he believed the crew should have waited until the sea was calm.

"It wasn't safe for them," he said. "The sea was quite choppy."

Koc added: "People died. It's not right."

He also said the boat had arrived in Kyrenia on Saturday and "had some damage in the front".

The ferry, a high-speed vessel 40 metres long and 10 metres wide, sails under the flag of Turkey, according to marine traffic data.

Filo Denizcilik, the company operating the capsized boat, said it was "deeply saddened by the tragic accident". A hotline has been set up to provide relatives of passengers with information.

The nationalities of those on board and the condition of the injured remain unclear. Local television broadcast images of the upturned ferry in the water, with people wearing life vests visible atop its hull.

The TRNC, recognised only by Turkey, controls the northern third of the island of Cyprus, which has been divided since 1974.