(WASHINGTON) - Israelis have presented what the Bush administration believes is "compelling evidence" that Yasser Arafat knew about a shipment of weapons intercepted by Israel, a senior State Department official told CNN.
"We now know enough to say that there were actions that occurred that we can only assume Arafat had knowledge of, could have been involved with," the official said.
The official said that "it was clear there were senior figures in the Palestinian Authority and Fatah involved."
The Israeli government has accused the Palestinian Authority of being behind the 50 tons of arms being shipped, which included Katyusha rockets, rifles, mortar shells, mines and a variety of anti-tank missiles.
The arms were found on board a ship captured last Thursday in the Red Sea about 300 miles south of the Israeli port of Eilat.
The Palestinian Authority has denied any involvement in the arms shipment, saying Israel is trying to use the incident to thwart efforts by U.S. envoy Anthony Zinni to broker a cease-fire between Israel and Palestinians.
The captain of the ship, who was arrested by Israel, told reporters Monday that, though he worked for the Palestinian Authority and that the shipment was to be delivered to Palestinians, he did not believe any Palestinian Authority leaders were aware of his mission.
The State Department official's comments followed a series of high-level briefings between senior Israeli intelligence officials and members of the Bush administration in Washington on Wednesday.
"We have had extensive briefings from the Israelis, and at the moment there is quite a bit of compelling evidence that figures Fatah and the Palestinian Authority were involved in this shipment, and it is clear that Chairman Arafat has a responsibility at this point to provide an immediate and clear explanation," the official said.
"We have concluded that part of these transactions and shipments were of such magnitude that we have to conclude that Arafat would have known," he said.
When asked what impact this might have on U.S. attempts to mediate a cease-fire and jump-start long-stalled peace talks, the official refused to answer directly.
Instead, he called on Arafat to "establish the facts" and "take action to prevent arms smuggling and escalation of violence."
"You need to take actions not only against groups on the outside" but within the Palestinian leadership, the official said. "We do see a reduction of violence on the ground, but you can't allow the potential for escalation of violence to occur."
U.S. Middle East envoy Anthony Zinni headed home Sunday after four days of intensive talks with Israelis and Palestinians in an attempt to get both sides to honor a meaningful cease-fire. He was due back in the Middle East next week.
An Israeli Cabinet minister said on Tuesday that the 3,000 pounds of plastic explosives and Katyusha rockets in the shipment would have imperiled every city in Israel.
The Katyusha is a ground-to-ground missile previously used by Hezbollah fighters in Lebanon for cross-border attacks on targets in northern Israel. It has a much greater range and destructive capacity than the weapons most commonly used by Palestinian fighters.
Israeli tanks and bulldozers, meanwhile, entered the Palestinian refugee camp at Rafah in southern Gaza and destroyed at least 30 homes, the Palestinian Authority said Thursday. The action was a response to an attack Wednesday by Palestinian gunmen, who cut through a security fence at an Israeli army post and opened fire, killing four Israelis before being slain themselves.
An account on the Palestinian news agency WAFA said Thursday that 12 tanks and four bulldozers, penetrated 100-200 yards into the Block "O" area in the Rafah refugee camp near the Salah El-Din Gate on the Egyptian border and started destroying homes.
The WAFA account said 31 families comprising approximately 200 people were displaced.
A spokesman for the Israel Defense Forces had no comment on the report.
The Islamic group Hamas claimed responsibility for Wednesday's attack, which shattered a recent lull in violence.
Hamas -- an Islamic fundamentalist group whose military wing, Izzedine al Quassam, has carried out military and terrorist operations against Israelis -- had announced on December 21 that it would suspend suicide attacks inside Israel. The announcement followed a speech by Arafat calling for a halt to violence, prompted by international pressure following a series of deadly bombings on Israeli civilians in early December.
At the time, the Israeli government dismissed the Hamas announcement -- calling it a "mixed message" -- and said Hamas remained a serious threat.
The IDF identified the dead as Maj. Ashraf Hawash, 28, from the Zarzir village, Staff Sgt. Ibrahim Hameida, 23, from the village of Rehaniya, Staff Sgt. Mofid Suad, 25, from the Abu-Snein village, and Staff Sgt. Abu-Ganem, 25, from Haifa.