Grabar-Kitarovic expressed deep concern and shock on the part of the Croatian government and public at Tuesday's action by the Indonesian military, the Croatian ministry said in a statement.
The Croatian minister cited serious implications of the act as well as a decision made by Indonesian judicial authorities in May this year under which the Indonesian Navy was to have escorted the Croatian ship "Mirna" to international waters, which it failed to do.
Grabar-Kitarovic said it was necessary to take into consideration economic and political aspects of the whole situation as well as the humanitarian aspect, notably the wellbeing of the ship's crew.
The Croatian minister requested that the crew, who are all nationals of Croatia, be immediately released and that the ship be allowed to leave for international waters. She also urged that those responsible for the act be sanctioned accordingly.
An official of the Croatian Embassy in Jakarta has visited the Croatian ship and seen that the captain and the crew are well, the statement said.