Eight members of the Islamist Hamas movement were arrested by Israeli troops on Tuesday in early-morning raids in the northern West Bank, Palestinian security sources said. They said that soldiers detained Hamas activists in the city of Nablus and the town of Tulkarem, among them Rafat Nassif, a former Hamas spokesman. The military said only that it arrested five Palestinians in Tulkarem, without giving further details. Last week Israel arrested 25 Hamas members in raids across the West Bank, three of them members of the Palestinian parliament. Palestinian security forces rounded up at least 25 more.