The Ministry of Foreign Affairs handed over the document to a representative from the Indonesian Embassy in Vietnam on Wednesday.

The document expresses Vietnam’s concerns over the incident on April 27 when Indonesia arrested a group of Vietnamese fishermen operating within Vietnam's waters, in an area where Vietnam and Indonesia are delimiting their exclusive economic zones (EEZs), 5.5 nautical miles north of the 2003 continental shelf delimitation line.

A Vietnamese fishing boat with 14 fishermen on board were arrested and towed away at high speed by Indonesian ship number 381, causing the Vietnamese boat to sink.

A Vietnam Fisheries Resources Surveillance's vessel discovered the incident while performing its duties in the area, rescued two of the fishermen and demanded that the Indonesian ship leave Vietnamese waters.

However, the remaining 12 fishermen were taken into Indonesian waters.

Vietnam’s ministry now insists that what Indonesia had done "seriously violated Vietnam's sovereignty and jurisdiction, and was contrary to international law, inconsistent with traditional friendship relations and the Vietnam - Indonesia strategic partnership, as well as the solidarity of ASEAN (Association of Southeast Asian Nations)."

The note requested Indonesia to strictly abide by the provisions of the 1982 United Nation’s Convention on the Law of the Sea (UNCLOS), to which both countries are members, and to direct its maritime functional forces to stop and not repeat the inappropriate actions of April 27.

It also demanded that Indonesia immediately release the crew of the sunk vessel, treat them humanely and make adequate compensation for the Vietnamese fishing boat and for the fishermen.

This is the second time Vietnam made its demand.

The foreign ministry had on Sunday sent a note to the Indonesian embassy but has yet to receive a response.

Last year, Indonesia destroyed 86 Vietnamese fishing boats for allegedly illegally catching fish in its waters. Vietnam has several times called on Indonesia not to use violations against Vietnamese fishing boats and fishermen in a manner that goes against the strategic partnership between the two countries.