An Indonesian search and rescue team has determined the location of a sunken ferry after 11 days of scouring the bed of the volcanic lake in North Sumatra it capsized on.

‘After 11 days of non-stop search at 12:39 pm [0540 GMT Thursday] we have detected an object and identified that it is part of KM Sinar Bangun,’ the chief of the national search and rescue agency, Muhammad Syaugi, told a press conference in Jakarta on Thursday.

The search team launched a remotely operated vehicle (ROV) and obtained clear photos and videos to determine the location of the ferry.

‘Through the ROV we can see clearly images of victims, motorcycles, and part of the ferry such as seats and ropes. It was detected at more or less 4.3 kilometres south-west of Tigaras port,’ Syaugi said.

‘Our challenge now is to evacuate the victims. We will consult with the families of the victims, the authorities and community leaders to determine our next steps,’ he said.

Earlier this week the rescue agency detected an object at a depth of 490 metres.

The ferry KM Sinar Bangun sank minutes after it set sail in bad weather on North Sumatra's Lake Toba on June 18. Of around 200 people on board the ferry, only 18 people have been rescued alive, including the boat's captain, who also owns the boat.

North Sumatra Police have charged four people, including port officials and the boat owner, for negligence and causing people's deaths.