GAZA, March 22 (UPI) -- Palestinian leader Yasser Arafat and leaders of Islamic militant group Hamas declared three days of mourning on Monday for the group's founder and spiritual leader, Sheikh Ahmed Yassin, who was assassinated at dawn by Israeli missiles as he was leaving a mosque near his home in Gaza City.
The 67-year-old paraplegic was killed when Israeli Apache helicopters fired three missiles at him as he was headed toward his car in his wheelchair following morning prayers. Residents in the neighborhood said that Yassin and his wheelchair flew into the air as dozens of people were leaving the Al Mujama' Mosque near Yassin's home in the Al-Sabra neighborhood of Gaza City.
Sources at Shiffa Hospital, where Yassin's body was taken, said that eight others were killed, including three bodyguards and five bystanders. Twelve people were wounded, including two of Yassin's sons. The hospital later added that four additional Palestinians were killed in clashes with Israeli soldiers following the attack.
Izel Dein Al Qassam, the armed wing of the militant Islamic Hamas movement, said in a leaflet that its response to the assassination of Yassin would be "like an earthquake that will shake all the state of Israel."
Leaders, members and supporters of Hamas rushed to the hospital to view Yassin's body, chanting slogans calling for revenge against Israel, and thousands of people poured into the streets as they heard the news.
"We strongly condemn this assassination of an old quadriplegic man," Palestinian Authority chief negotiator Saeb Erekat told reporters at the hospital. "Israel is dragging the whole region again to a wave of violence."
Erekat added, "Israel knows very well that the assassination of Sheikh Yassin would not bring any solution."
One day before the killing Israeli Defense Minister Shaul Mofaz had said he considered Hamas "a strategic enemy," and on Monday Deputy Defense Minister Zeev Boim said Yassin deserved death. The Israel Defense Forces spokesman Monday confirmed the army had targeted Yassin in Gaza.
A statement by the defense forces said: "This morning, in a security forces operation in the northern Gaza Strip, the IDF targeted a car carrying the head of the Hamas terror organization, Sheikh Ahmed Yassin and his aids. Yassin, responsible for numerous murderous terror attacks, resulting in the deaths of many civilians, both Israeli and foreign, was killed in the attack."
Last week two suicide bombers killed 10 Israelis in Ashdod, and Mofaz told the Israeli cabinet that seven more suicide bombings had been thwarted since the beginning of March.
"We have decided to create a counter wave of continuous pressure," Mofaz said. "Hamas and its leaders, definitely Sheikh Yassin, saw their goal as the total destruction of the state of Israel."
Yassin was born in 1936, in the village of Al Joura, near the city of Ashkelon before the establishment of the state of Israel. He and his family left the village during the 1948 war and went to Gaza as refugees.
Yassin was arrested by Israel in 1984 for possession of weapons, but was released in a prisoner deal with the Palestinians in 1985.
He was again arrested in 1989 and sentenced to life in prison, accused of ordering the kidnapping and killing of two Israeli soldiers. He was released in 1997, in exchange for two Mosad agents arrested in Jordan after attempting to assassinate a senior Hamas leader in Amman.
"The reaction to assassinating the Sheikh will turn all Palestine (including Israel) to an angry volcano and into a piece of hell that will burn the land under the feet of the Zionists!" Islma'eel Haneya, a Hamas leader close to Yassin, told reporters at Shiffa Hospital.
"Yassin is a martyr and he is in paradise now," Haneya said. He said that reaction "to this awful crime would never be expected, and Israel would severely regret assassinating (Yassin) and other Palestinian leaders and fighters."
Within hours of Yassin's death, Izel Dein Al Qassam fired several medium-range homemade rockets at southern Israel. The group said in a leaflet that the rocket attack was only the first reaction to Israel's attack on Hamas. There were no reports of damage caused by the missiles.
The Israeli army imposed a complete closure on the Palestinian territories, as mosques in Gaza and the West Bank called for a 3-day general strike.
Schools in Gaza City were deserted as thousands of schoolchildren and university students headed to the hospital where Yassin's body lay, or to his home in the Sabra neighborhood.
Flames and black smoke billowed in the air as angry Palestinians burned tires in the streets, while thousands of marchers filled the streets of Gaza City as well as towns, villages and refugee camps throughout the Palestinian territories.
The different Palestinian armed groups vowed to escalate their attacks on Israel.
(Joshua Brilliant in Tel Aviv contributed to this report.)