JERUSALEM  - Israel enforced a curfew in the West Bank village of Nilin on Sunday after dozens of people were wounded in weeks of protests against a proposed extension of its controversial separation barrier. "Since this morning there has been a curfew in Nilin due to the significant rise in violence near the Palestinian village," an Israeli military spokesman said on Sunday. "For over two months violent riots have taken place in Nilin." The spokesman added that there was no time limit on the curfew and that it would remain in effect until the violence stopped. Dozens of demonstrators have been wounded during protests in recent weeks, and on Sunday alone 13 Palestinians were treated for rubber bullet wounds and dozens more for tear-gas inhalation, according to local medics. Israeli troops on Sunday placed concrete blocks and signs reading "closed military zone" across roads leading into town and prevented local reporters and photographers from entering. The protests have been aimed at a proposed extension of Israel's controversial separation barrier, which villagers say will rob them of some 2500 dunams (250 hectares) of land near the proposed route. The demonstrations have been modelled on those of the nearby village of Bilin, where residents have protested the barrier on a weekly basis for over two years and in September won a court injunction against its proposed route. Meanwhile, Israel reopened border crossings to the Gaza Strip on Sunday that were closed when a rocket was fired from the Hamas-ruled territory in defiance of a two-week-old truce. "The Sufa, Nahal Oz, and Erez crossings are open for the passage of goods, including cement and fuel," Israeli military spokesman Peter Lerner told AFP, adding that Erez was also open for sick Gazans requiring treatment in Israel. Israel took the decision to reopen the crossings because there had been no further rockets or mortar rounds launched from Gaza since an attack on Thursday despite a truce that took effect on June 19, Lerner said. On Sunday, a gunshot was fired from the Gaza Strip at a farmer driving a tractor near the Nahal Oz fuel terminal, according to the Israeli army. "There was some kind of shooting from a light weapon at a civilian doing agricultural work near Nahal Oz," a military spokesman said. No one was wounded, but "they damaged a tractor working in the area," he said. Tensions remain high in the battle-scarred fields along the Gaza border, where Israeli troops have fired warning shots at farmers which Palestinian and UN officials say have wounded at least two people since the truce began.