It's the abbreviation for Access and Closure Information System and it's run by the Office for the Coordination of Humanitarian Affair of the United Nations.
The form to be used for reporting an incident is below. Notice the category "settler":-
If you'd like to express your opinion about this procedure or have any questions, you can contact the UN in Jerusalem at
United Nations Office for the Coordination
of Humanitarian Affairs (OCHA) [rhymes with 'gotcha']
(7 St. George Street)
Tel. 02-5829962; 5825853
You might want to ask them if they have forms for revenant Jews who are suffering terrorism, rock-throwing, molotov cocktail tossing, roadblocks, Kassam missiles, AK-47 shootings, etc.