The IDF has arrested the sister of the Palestinian terrorist who murdered a 13-year-old Israeli girl in her bed in the West Bank settlement of Kiryat Arba on Thursday, the military said Sunday.In overnight raids in the West Bank between Saturday and Sunday, the sister of Muhammad Tarayrah, 17, who stabbed Hallel Yaffa Ariel to death in her sleep was arrested on suspicion of incitement and encouragement of terrorist activities. Tarayrah was shot and killed at the scene of the attack. Along with Tarayrah's sister, Israeli forces arrested five other Palestinians, including a nurse, during the raids carried out in Hebron and the Palestinian villages of Fawwar, Bnei Naim, al-Burj and Khirbat al-Hijra.The IDF on Sunday continued to blockade the Hebron region and conduct intensive sweeps.After the attack in Kiryat Arba on Thursday, Prime Minister Benjamin Netanyahu and Defense Minister Avigdor Liberman met and ordered the IDF to close off the Palestinian village of Bani Naim, located near Kiryat Arba, where Tarayrah lived. They also ordered the IDF to rescind work permits belonging to Tarayrah’s immediate and extended family.Throughout the weekend, the Hebron region continued under IDF closure – the first such security measure in two years – as security forces conducted a mass search for the terrorist shooting cell that fired on an Israeli vehicle on Friday, killing Rabbi Michael Mark, a father of 10.The closure is part of an effort to disrupt a series of deadly terrorist attacks on Israelis over the past few days, a senior security source said on Friday. Only humanitarian journeys are allowed out of the city and its suburbs, which are home to some 700,000 Palestinians, for the duration of the closure.Yaakov Lappin contributed to this report.