Iran warned Israel on Friday not to launch a ground offensive into the Gaza Strip as protests against the Israeli bombardment of the Hamas-run Palestinian territory, now in its seventh day, swept several Mideast capitals. The demonstrations began shortly after Friday prayers in Teheran, Cairo, Amman and Damascus. Similar protests have been held daily across since Israel launched the bombing campaign last Saturday, but these gatherings were larger _ mainly because Friday prayers are a traditional opportunity for Muslims to assemble in great numbers. In Teheran, a crowd of about 6,000 stretching for a half-mile (kilometer) marched from prayers at Teheran University to Palestine Square, chanting "Death to Israel" and "Death to America" and burning Israeli flags They also carried banners reading: "Don't kill Children" and "Real Holocaust is happening in Gaza," while some vowed to "fight and defend Gaza." Ayatollah Akbar Hashemi Rafsanjani, one of Iran's most powerful politician-clerics, said in a sermon to several thousand worshipers that an Israeli military defeat in Gaza would be a "scandal" for its government and that, even if the Hamas government there collapses, Palestinian "resistance" will only expand. Iranian Foreign Minister Manouchehr Mottaki warned Israel that entering Gaza "by land will be the biggest mistake of the Zionist regime." He vowed Israel would be "defeated" in a ground attack. Iran is a major backer of Hamas, giving it millions of dollars. Israel and the US accuse Iran of providing the Palestinian terrorist group with newer, more sophisticated rockets, but Teheran denies arming the group. In his prayer sermon, Rafsanjani said Hamas had a new anti-tank weapon that it had not used before but would unleash if Israel ground troops move in, but he did not elaborate. US-allied Arab governments like Egypt fear that Hamas and Hizbullah are giving a foothold for Iran. They have been critical of Hamas - which took over Gaza in 2007 in battles with loyalists of Palestinian Authority President Mahmoud Abbas - and of Syria for backing its allies Iran and Hamas. Pro-US governments have been wary about protests at home over Israel's Gaza assault, which has killed more than 400 Palestinians and sparked outrage among the Arab public. Israel says its offensive aims at silencing Hamas rockets. In Jordan, police fired volleys of tear gas and scuffled with dozens of protesters who tried to push through barrier to reach the Israeli Embassy in Amman. A few of the protesters threw stones at police, but the security forces dispersed the group, arresting several. Hundreds more protesters marched peacefully nearby the embassy, calling for its closure and the expulsion of the Israeli ambassador. Jordan and Egypt are the only two Arab countries with peace agreements and diplomatic relations with Israel. Egypt clamped down hard to prevent protests Friday. Hundreds of riot police surrounded Cairo's main Al-Azhar Mosque, where a rally had been called, and scuffled with would-be protesters, keeping most from approaching. At another Cairo mosque dominated by the opposition Muslim Brotherhood, police set up security checkpoints and inspected worshipers' ID cards. Around the capital, police arrested 40 members of the Brotherhood, which had called for pro-Gaza rallies. In the southern Cairo suburb of Maadi, one mosque preacher called for holy war for Gaza and several protesters marched nearby, shouting: "Let us go to jihad," or holy war. More than 3,000 people marched in solidarity with Gaza in the northern Sinai city of el-Arish, Egypt's closest city to Gaza. On the border, dozens of Sinai Beduins raced around in cars in the town of Rafah, firing their guns into the air. In Syria, some 2,000 marched in Damascus' Palestinian refugee camp of Yarmouk, carrying Palestinian flags and chanting "jihad will unite us," and later burned an Israeli flag. Several hundred Syrians also protested in Damascus' historic Ummayad Mosque, waving green Hamas banners and wearing Hamas headbands. In Sudan, thousands marched in downtown Khartoum from mosques to the main Martyrs Square, urging Muslims to jihad and denouncing Israel and America. Also in Teheran, a small group of students protested late Thursday outside the house of 2003 Nobel peace laureate Shirin Ebadi, accusing her of supporting Israel. They vandalized the house, smashing a sign and spray-painting the walls. Ebadi has been a target of Iranian hard-liners because she accuses the government of human rights violations.