Updated

Armed Hamas militants vowed huge attacks against Israel at a rally Wednesday marking the end of three days of mourning for the Islamic militant group's assassinated founder Sheik Ahmed Yassin (search). "Wait for the earthquake," one masked man warned.

Tens of thousands streamed to Gaza City's Yarmouk soccer stadium in another show of strength for Hamas. On Monday, about 200,000 people filled the streets of Gaza City for Yassin's funeral procession.

The huge rally Wednesday reflected Palestinian anger and support for Hamas, which has killed hundreds of Israelis in homicide bombings and other attacks over the past 42 months.

Hamas is the main rival of Yasser Arafat's Palestinian Authority (search), which has been relegated to secondary roles in Gaza since Israel killed Yassin with a missile strike on Monday. Palestinian Prime Minister Ahmed Qureia (search) briefly visited the stadium Tuesday to offer condolences.

A huge TV screen showed the proceedings inside the stadium, featuring the new Hamas leader in Gaza, Abdel Aziz Rantissi (search), flanked by other Hamas notables.

One masked man, armed with an M-16 rifle and wearing a green bandanna on his head, spoke for the commanders of the Hamas military wing, called Izeddine al Qassam. He threatened punishing retaliation for Israel's killing of Yassin.

"Our message to the Zionists is ... wait for the earthquake, one like you have never seen before, the earthquake reprisal," he said. "Operations like they have never seen with their eyes." He did not identify himself.

Delivering a message from Mohammed Deif, a senior militant who has escaped several Israeli attempts to kill him, the masked man pledged allegiance to Rantisi.

Then all the people in the stadium raised their right hands and recited a pledge that began, "What are your wishes? To die for the sake of God."

About 400 uniformed Hamas militants armed with a variety of rifles marched into the stadium and lined up in front of the crowd, as people threw flowers and candy at them.

In Beirut, Arabs protested for a third day against the killing of Yassin, pushing an empty wheelchair at the head of a column of about 7,000 people to remember the paraplegic Hamas leader.

Some 7,000 Egyptians attended a memorial in Cairo for Yassin called by opposition parties.

At a refugee camp outside Damascus, Syria, about 200 Palestinian women shouted for Hamas's military wing to "take revenge for the martyred sheik."