TEL AVIV, Israel – Iran has taken control of many Palestinian Arab terrorist cells from Yasser Arafat’s Fatah movement, giving them funds and orders to attack Israeli targets, and even rewarding successful missions with “bonuses,” according to a senior Israeli security source.

For many years, Iran has given money and ideological support to radical Palestinian Arab groups, especially Hamas and Islamic Jihad, responsible for most of the Israeli deaths in the past four years of the Palestinian uprising.

But Israel believes that much of the Fatah-affiliated armed faction, calling itself the Al Aqsa Martyrs Brigade, has now come under Iran’s sway, especially in the West Bank.

Scores of Palestinian Arab attacks, accounting for roughly one-third of the 98 Israelis killed so far this year, are believed to have been orchestrated by Lebanon’s Hezbollah movement.

The Shiite group pioneered the use of suicide bombings in the 1980s, kidnapped Westerners, and successfully drove the Israel Defense Force out of south Lebanon in 2000. Hezbollah is now a political party in Lebanon.

“Hezbollah is a finger of Iran’s hand,” the senior Israeli security source said. “In the past year, we can see increasing Iranian influence in Palestinian attacks on Israel. The same people sometimes receive money both from Mr. Arafat’s headquarters and from Hezbollah. If the attack succeeds in causing fatalities, they get a bonus from Hezbollah.”

Another security source said Hezbollah rewards Palestinian Arab cells to the tune of $5,000 for each Israeli killed.

Israel regards Tehran as its mortal enemy, and has every interest in presenting Iran as a dangerous state sponsor of international terrorism. But on the issue of penetrating Fatah, Israel is in unusual agreement with Palestinian Arab leaders.

Mr. Arafat, the Palestinian Arab leader who has been confined to his Ramallah headquarters for more than three years, said this week that Hezbollah was trying to infiltrate Fatah.

He said Iran was financing radical Islamist groups, and denounced Iran’s spiritual leader, Ali Khamenei.

He said: “Khamenei is working against us. He is giving money to all these fanatical groups. Khamenei is a troublemaker.”

Mr. Arafat implied that he retains control of Fatah cells. But Israel believes many of his armed followers are being directed by Hezbollah after many cells were broken up during Israel’s re-invasion of West Bank cities in April 2002.

The security official said Hezbollah had a team of 10 “controllers” in Beirut dedicated to overseeing the cells.

“Since Arafat’s headquarters was destroyed and people were arrested, local cells have had no leadership,” he added.