A group of 65 Rohingya Muslims have been found on a shipwrecked boat off the coast of southern Thailand, Navy officials said on Wednesday. The boat was discovered early Tuesday in the Tarutao Marine National Park in southern Thailand, around 400 kilometres from the border of Myanmar. Some 740,000 Rohingya Muslims have fled Myanmar since a brutal military crackdown in 2017 against the minority in the Buddhist-majority country. Most have escaped to overcrowded refugee camps in Bangladesh, while others have fallen prey to human trafficking rings as they seek better lives in Malaysia or Thailand. A Thai Navy spokesman said there were 31 women and five children among the Rohingya on the shipwrecked boat. Authorities are investigating whether they had been trafficked. One Thai man and five Burmese citizens were also in the group. The men said they were fishing in the area and had no link to the Rohingyas. The six men "were detained for questioning because of their suspicious behaviour," Thai Navy spokesman vice admiral Khan Deeubol said on Wednesday. A provincial official said the group was initially investigated for illegal entry but the probe had broadened. "Authorities are not ruling out other issues such as human trafficking," an Internal Security Command source in Satun province told AFP. Bangladeshi authorities have intercepted several suspected traffickers transporting refugees from squalid camps in Cox's Bazaar, where nearly one million Rohingyas are living – almost all refusing to go back to Myanmar out of fear for their safety and rights. Myanmar has said the 2017 crackdown was aimed at rooting out insurgents who attacked military posts. It has signed a repatriation agreement with Bangladesh to bring back Rohingya refugees, but so far very few have volunteered to return. United Nations investigators have said the violence amounts to "genocide" and called for the prosecution of top generals.