Israeli security forces have arrested five Palestinians who orchestrated an explosive attack on a Jerusalem bus in April, the Israeli army said on Sunday.At least 21 Israelis were injured in the explosion on the bus in Jerusalem on April 18, Xinhua news agency reported.The group members, said to be associated with the Hamas organisation, were involved in planning and recruiting the militant for the attack, and manufacturing the explosives, the Israel Defence Forces (IDF) spokesperson said in a statement.The Shin Bet security agency said in a separate statement that two Palestinians from the group carried out a shooting attack recently in the Jewish settlement in the West Bank of Tekoa, and no injuries were reported.The agency said the group also planned to carry out more attacks against Israeli citizens and soldiers.The five arrested Palestinians will be filed against them by the military prosecution in the upcoming week.The attack took place amid an ongoing wave of violence between Israelis and Palestinians, which had claimed the lives of 28 Israelis and 204 Palestinians since October.Israeli leaders blame the Palestinian Authority for incitement to violence amid the wave of unrest, whereas the Palestinians charge it the result of the 49 years of Israeli occupation of the West Bank, East Jerusalem and Gaza Strip territories, where they wish to establish an independent Palestinian state.