Activists aboard a Gaza-bound aid flotilla said Israeli warships surrounded several of its boats on Wednesday evening and that the interception of the main vessels was under way. "The warships are moving in to intercept the flotilla -- only 81 nautical miles remain to Gaza," said the Maghreb contingent of the Global Sumud Flotilla in a statement. Earlier on Wednesday the Israeli navy said it had warned the flotilla to change course as the vessels approached waters under an Israeli blockade. "The Israeli Navy has reached out to the... flotilla and asked them to change course," the Israeli Defence Ministry said in a statement. The flotilla organisers had said however that they would stay the course despite "intimidation tactics" by the Israeli military.