JERUSALEM  - The Israeli authorities set a “red line” of minimum food needs for the Gaza Strip so that a punitive military blockade would not cause malnutrition, an Israeli NGO said in a report. Gisha, which campaigns for Palestinian freedom of movement and trade, said that defence ministry documents dating from 2008 and obtained under a freedom of information suit showed that an average of 2,279 calories per person per day was deemed sufficient. Israel first imposed a blockade on Gaza in June 2006 after militants there snatched one of its soldiers. It was tightened in September 2007 several months after the Islamist Hamas movement seized power, ousting forces loyal to Western-backed president Mahmud Abbas.