The Israeli military has ordered the expulsion of 15 Palestinian detainees from the West Bank to the Gaza Strip.
Kifah and Intisar Ajouri were expelled for helping their suicide bomber brother
The decision was immediately condemned by Palestinian Prime Minister Ahmed Qurei as a flagrant obstruction of efforts to restore calm in the Middle East.
Correspondents say the decision is unprecedented in its scope, with similar expulsions taking place only once before.
Last year, three relatives of Palestinian suicide bombers were moved from the West Bank to Gaza in the hope of deterring further attacks.
The practice of forcible expulsions has been denounced by human rights groups, who say it runs contrary to international law.
But last year's expulsions were sanctioned by Israel's Supreme Court.
The BBC's Jerusalem correspondent, Barbara Plett, quotes military sources as saying the decision to reinstate the practice was made in the wake of the recent Haifa suicide bombing which killed 19.
Military sources say the 15 candidates for expulsion were all captured in the West Bank and represent a range of Palestinian militant groups, including Hamas and Islamic Jihad.
Our correspondent says the 15 are suspected of aiding anti-Israeli attacks, but none are accused of being directly involved in the killing of Israeli citizens.
Chance to appeal
The detainees have been given 48 hours to appeal against the decision, but in the meantime have been moved to a detention facility at the Erez Crossing on the edge of the Gaza Strip.
General Moshe Kaplinsky, the Israeli soldier in command of the central region which includes the West Bank, signed the expulsion order for "15 administrative detainees implicated in terrorist activities", the AFP news agency reported.
"This measure has been taken in order to reduce the number of anti-Israeli attacks which have recently taken place," military sources were quoted as saying.
Israel has threatened Arafat with exile recently
Israeli army radio reported that the group would be transferred to an Israeli detention centre inside the Gaza Strip before being released - although once freed they will not be allowed to leave Gaza.
News of the expulsion plan came just hours after Israeli troops, backed by about 40 tanks and helicopter gunships, raided the Rafah refugee camp in Gaza in the second large-scale incursion in less than a week.
Palestinian medical officials say at least three Palestinians have been injured in the operation, which the Israeli army says is aimed at destroying tunnels used to smuggle weapons into the camp from neighbouring Egypt.