Yangong: More than 700 migrants found packed aboard an overcrowded boat in the Andaman Sea were still being held offshore by Myanmar's navy on Monday, more than three days after the converted fishing vessel was intercepted off the country's coast.

‘The government is checking their identity, asking what they want to do and where they want to go,’ government spokesman Ye Htut told Reuters, without providing further details of the boat's location.

‘Usually, most of them want to go back to Bangladesh, so we will arrange according to their wishes.’

Government officials have been tight-lipped about the identities of 727 migrants on the overcrowded fishing boat, found drifting and taking on water early Friday, as well as their eventual destination.

The government initially labelled the migrants ‘Bengalis’, a term used to refer to both Bangladeshis and Rohingya Muslims, a largely stateless minority in Myanmar that the government refuses to refer to by name. Officials later said they believed most of those on board were from Bangladesh.

Myanmar has come under harsh criticism for its treatment of Rohingya, more than 100,000 have fled persecution and poverty in Rakhine State since 2012. Myanmar denies discriminating against the Rohingya.

Journalists from Reuters and other foreign media were briefly detained and turned back to land after approaching the boat on Sunday, as it was seen surrounded by navy patrol vessels.

Navy officials made journalists delete photographs and footage of the boat, and at one stage a sailor pointed a rifle at reporters.

A navy officer, who declined to be named, told Reuters on Sunday that some migrants on board were able to speak Rakhine - a local language in the western state that is not widely spoken in Bangladesh.

Myanmar's government says the Rohingya are illegal migrants from neighbouring Bangladesh, and has denied it is to blame for a crisis that has seen more than 4,000 Rohingya and Bangladeshi ‘boat people’ arrive across Southeast Asia in recent weeks.

The migrants were abandoned at sea by people smugglers after Thailand launched a crackdown on trafficking in early May.

Myanmar officials had said last month that another migrant boat found at sea with more than 200 people on board was mostly filled with Bangladeshis.

But interviews by Reuters found more than 150 Rohingya had earlier been on the same boat, but were quietly whisked off by traffickers before authorities brought the boat to shore.