GAZA, Sept 13 (Reuters) - Hamas's government in the Gaza Strip called on Thursday on Palestinian militants to stop firing rockets and mortar bombs at border crossings with Israel that are used to bring food and other supplies into the territory. A government spokesman said the rocket and mortar attacks should be stopped to "preserve the interest of the Palestinian people", especially during the Muslim fasting month of Ramadan. Militant groups said they would consider the request but had no intention of stopping rocket fire into Israel during the holy month, which began this week. Gaza's main border crossings have been closed since Hamas took over the coastal strip in June. But Israel allows aid groups to use smaller crossings, including Kerem Shalom, Nahal Oz, Erez and Sofa, to bring in food, medicine, fuel and other basic supplies for Gaza's 1.5 million residents. Rocket attacks on these crossings have forced aid groups to temporarily call off some shipments. It is unclear whether militant groups will heed Hamas's call to stop the attacks. Khader Habib, an Islamic Jihad leader, said the group would study the request. A rocket attack earlier this week injured at least 35 Israeli soldiers at an army base next to Gaza, prompting calls within Prime Minister Ehud Olmert's government for tougher reprisals. One militant group aligned with Hamas, the Popular Resistance Committees, said it began what it called its "Death Campaign" to intensify rocket fire into Israel throughout the month of Ramadan.