A university student, who went missing in the sea off the St Martin's Island over a year ago, is believed by parents to be among the boatpeople recently rescued in Indonesia.

"That's our son, we are sure about it," Hasanur Rahman, father of missing Sabbir Hasan, said pointing at a youth in a photograph of the migrants rescued in Indonesia.

Sabbir, who would now turn 23, and his friend Ishtiaque Bin Mahmud Udoy, both students of Ahsanullah University of Science and Technology, went on a trip to the island along with 32 fellow students in April last year to celebrate the Bangla New Year.

A joyful trip turned tragic in a simple twist of fate when six of the students drowned in the sea on April 14. Four bodies were recovered but those of Sabbir and Udoy could not be found.

Around 14 months after the tragic incident, when Sabbir's parents saw the AFP photograph in a newspaper on May 11, they came up with the startling claim.

"This is my son ... I can recognise him even from afar," Sabbir's mother Shelina Akther said, pointing at an emaciated man lying on a plastic sheet in the photo.

"This is how my son sleeps … He has become very thin."

"Something deep inside me tells me that Sabbir, my dearest son, isn't dead. We'll get him back alive," the mother told The Daily Star at their Mohammadpur residence in the capital yesterday.

Soon after seeing the photo, they had contacted the foreign ministry and sought help in rescuing who they believe was their missing son. They also had emailed a photo of Sabbir to the Bangladesh mission in Indonesia the same day.

In response, State Minister for Foreign Affairs Shahriar Alam on Wednesday told the parents that they had identified a total of 422 Bangladeshis among the trafficking victims at a camp in Aceh, but Sabbir was not among them.

"I called on his [the state minister's] phone and briefed him on what we had done in the past two weeks," said Sabbir's father Hasanur Rahman, a retired public servant.

The state minster has assured them of taking "all possible measures" to identify Sabbir, he added.