In the aftermath of the first Palestinian suicide bombing in more than a year, many Israelis have returned to an old conclusion: build a barrier.

Some politicians said that the answer to Monday's attack on the southern town of Dimona was to resurrect an existing, but never-implemented, plan to build some combination of a wall and fence between Egypt and Israel. The barrier would be similar to the West Bank wall that Israel started erecting more than six years ago, at a time when there was an almost nonstop cycle of violence between Israelis and Palestinians.

That separation barrier, which Israelis call a fence and Palestinians call a wall (it's actually a combination of both and a collection of watchtowers, gates, cameras, surveillance roads, and checkpoints), has never been completed. Amid questions as to whether it was really necessary and economically feasible to complete the barrier, the Defense Ministry told the 10 contractors building it to stop last November for lack of funds.

Following Monday's bombing, however, which the Israeli security establishment said it had more or less expected as a result of last month's break in the border wall separating Gaza from Egypt, senior Israeli leaders promised that they would see to the resumption of plans to build a high-security barrier along the 137-mile border with Israel and Egypt. Such a barrier could cost between $560 million and 835 million.

Defense Minister Ehud Barak, who is arguing anew for the construction of the Egypt barrier, said that the most realistic target date for completion is 2010. However, National Infrastructure Minister Benjamin Ben-Eliezer said Tuesday that Israel should race to complete it by the end of the year.

"We need to move faster on this project. It's a clearly marked border. We just need to bring in a contracting company right away to suggest how to do it," Mr. Ben-Eliezer said in an interview on the Voice of Israel Radio.

However, conflicting news reports in the past 24 hours have sowed confusion about the actual identity of the Palestinian suicide bombers – and more important, where they originated from.

The Al-Aqsa Brigades in Gaza, a militant offshoot of the Fatah faction of the Palestine Liberation Organization (PLO), was the first to claim responsibility for the bombings, and even distributed the names and presuicide videos of the young men who had set out during the days of the Gaza-Egypt border breach to make their way toward targets in Israel.

But Hamas has since claimed responsibility for the bombers and said Tuesday that they were actually from the southern West Bank city of Hebron.

Still, the likelihood that the bombers actually came from Hebron and not from Gaza only seemed to further Israeli arguments to resume construction of the West Bank barrier.

Several areas of the barrier that Israel began building in 2002 are unfinished, including two major areas in the south Hebron Hills as well as certain areas around Jerusalem.

Israel moved ahead with the project despite great international critique and a ruling at the International Court of Justice in The Hague that the line of the barrier – which in many places goes well beyond the pre-1967 boundaries, or the Green line – was illegal. Today, the wall remains finished in several key areas: in the region known as the South Hebron Hills and several areas around Jerusalem.

As of last November, the Israeli prime minister's office said that the budget for completing the barrier had run out. Several parts of it are still being challenged in court, with groups of Palestinians and human rights activists waging a legal battle against specific stretches of the barrier, while other parts were still in the planning stages when construction tapered off.

Gabriel Sheffer, a political scientist at the Hebrew University of Jerusalem, notes that the concept of Israel building a barrier between its territory and Egypt's is not controversial because there's no border dispute since the two countries made peace in 1979.

The south of the country, which was long seen as a rather safe and quiet region, is now being viewed by Israel as a region under fire: first by Qassam rockets launched by militants in Gaza, and second, by the sense of increased vulnerability to suicide bombings.

The crisis between Gaza and Egypt has raised tensions on both sides of the border. On Tuesday, Egyptian police rounded up about 2,000 Palestinians in Sinai a day following clashes that led to the death of one Palestinian and nearly 60 injuries, Reuters reported. Palestinians launched several Qassam rockets at Israel's southern town of Sderot, hitting one house and injuring at least one person. Israeli air raids Tuesday killed at least six Palestinians in the Khan Younis area of Gaza.

Israeli security forces are warning of additional bombing attempts and say that during the nearly two weeks in which the Gaza-Egypt border was open, longer-range rockets and missiles were brought into Gaza.

"I can't see how these activities will stop, and so the demand to finish the fence – both fences – will grow," says Professor Sheffer.

He said part of the reason for the flare-up was Defense Minister Barak's decision to shut Gaza off from goods, fuels, and electricity, adding, "Blowing the fence up was a direct reaction to what Israel did."