A Tunisian military probe into the sinking of a migrant boat in October that killed 46 people has blamed the captain of a naval vessel which struck it, the presidency said Friday.

The deaths of the Tunisian migrants trying to reach Europe was at the time called a "national catastrophe" by Prime Minister Youssef Chahed.

"The captain of the military ship and the captain of the (migrant) boat are accused, after their responsibility has been proven in this incident," the presidency said in a statement, after being informed of the results of an inquiry led by the military prosecutor's office.

The defence ministry and the prosecutor, contacted by AFP, were unable to confirm whether the two men had been formally charged or detained.

The tragedy took place on 8 October off the city of Sfax, with some of the 38 survivors accusing the military of deliberately ramming their boat after insulting them.

A defence ministry spokesman said the military vessel had followed the migrant boat for three and a half hours in an effort to convince it to turn back.