No one knows whether he died by bullet or bomb, but in the Middle East mutual suspicion reigns

By LISA BEYER /JERUSALEM

here were many ways for Muhi a Din Sharif to die. A fugitive living underground, he was wanted by both Israeli and Palestinian security for his alleged role in a spate of deadly explosions. And he labored in a dangerous line of work--the actual construction of the bombs. So when his body was found near the wreckage of a blown-up West Bank bomb factory last week, it was unclear who, or what, had claimed his life: his Israeli enemies, his Palestinian brethren or, perhaps, a "work accident." Palestinian authorities claimed Sharif was shot first, since his body contained three bullets, though these may have been part of the debris sent flying in the blast. But whatever the cause, one thing was plain to all: that explosion would not be the last connected with the life and death of Muhi a Din Sharif.

After Sharif's shattered body had been positively identified, Israeli security officials braced for a renewal of the terrorist bombing campaign that has claimed the lives of 155 victims in five years. Israel's assassination of Hamas bombmaster Yehia "The Engineer" Ayyash in 1996 triggered a wave of suicide attacks. Both Israeli and Palestinian officials denied involvement in Sharif's demise, but some in the militant organization Hamas blamed both sides and vowed vengeance. In fact, his death merely provides justification--and timing--for what Hamas has been struggling to do anyway: break the relative calm of the last seven months and get back to mayhem.

The last major terrorist attack was in September, when two suicide bombers killed five people in a pedestrian mall in Jerusalem. The quiet since then, Israeli security officials say, has been misleading. Hamas militants, they claim, have had a spate of failures in attempts to pull off new assaults. Behind the attacks--and the failures--are changes within the organization that have the potential to make it more deadly than ever.

According to Israeli and Palestinian sources, the West Bank branch of Izzaddin al-Kassam, the military wing of Hamas, recently has split from the group's leadership in the Gaza Strip. Says one Hamas guerrilla in the West Bank, "We are no longer waiting for the orders to come from Gaza." A colleague in the Gaza Strip called talk of a split "ridiculous," but added: "I know there are independent ideas on the interpretation and application of orders." Hamas insiders say that the West Bankers grew frustrated with the relative moderation of the Gaza hierarchy, who tend to take the view that it is better to refrain from violence than to risk further crackdowns by Palestinian leader Yasser Arafat.

But the West Bank commander of Izzaddin al-Kassam, Adel Awedallah, is said to be hungry for action. "He knows his days are numbered," says a ranking Israeli army officer based in the West Bank. "We're after him, the Palestinians are after him, and he's trying to do everything he can before one of us catches him, dead or alive." The Israelis rank Awedallah No. 1 on their wanted list for the West Bank. Sharif, who functioned as Awedallah's chief operations officer, was No. 2.

Awedallah, the Israelis believe, has fundamentally changed the modus operandi of his outfit. Previously, each Hamas cell, numbering up to 10 men, was given a single, specific assignment: to bomb a bus, kidnap a soldier or shoot a settler, for example. Under Awedallah's command, according to Israeli intelligence, the cells are instructed to work on many missions simultaneously--to attempt whatever they can whenever they can. "He's working on a mass scale," says the Israeli army officer. Intelligence officials say that now, even if they uproot a particular cell, they can no longer assume its mission is thwarted. "This has given us a few more white hairs," says the officer.

So far, security forces have been lucky. Last month, Palestinian security captured two suicide bombers in the West Bank who had been given explosives, destinations and orders to act within three days. One was directed to blow up Tel Aviv's central bus station. Two weeks ago, an apparent attempt to kidnap a hitchhiking Israeli army officer was averted when the officer, after accepting a ride from two men, grew suspicious of the front-seat passenger's Hebrew. Looking over the man's shoulder, the officer saw him reading from a prepared script and he leapt to safety from the moving car.

Israeli officials have responded to the new threat by issuing alerts, heightening security in crowded places and intensifying intelligence-gathering operations. But in the atmosphere of vengeful fury aroused by Sharif's death, even the most optimistic among them do not expect the quiet to hold indefinitely. Not with an enemy so devoted. Not with a motive so plain.

--With Reporting by Jamil Hamad /Gaza Strip and Aharon Klein /Jerusalem