Egyptian authorities, already struggling with elusive terror cells in the rugged Sinai Peninsula, moved quickly Tuesday -- arresting 30 men in the triple bombings that ripped apart a crowded resort town, killing 24 on a tranquil holiday evening.

Radical Muslim groups moved just as rapidly to distance themselves from the Dahab attacks. The leader of Egypt's banned Muslim brotherhood condemned them as "aggression on human souls created by God."

The militant Palestinian Hamas organization called them a "criminal attack which is against all human values."

Many frightened tourists fled Sinai coastal resorts where two previous bomb attacks -- like the Dahab blasts -- bore the hallmarks of Al Qaeda-linked groups that appear to have a free hand to continue operations in the barren, backward and extremely rugged Sinai Peninsula.

Egyptian authorities -- despite massive sweeps by thousands of troops and hundreds of arrests after each previous Sinai attack -- appeared increasingly frustrated by the ease with which terrorists continue to hit the country's vital tourism industry. It brought in $6.4 billion in 2005 and is the top source of foreign exchange.

"This incident is addressed to the whole of Egypt, there is no reason for it other than an attempt to destroy the economy of Egypt by attacking tourism," said Prime Minister Ahmed Nazif as he visited blast victims in a Sharm el-Sheik hospital.

President Hosni Mubarak, who oversees an already-stagnant economy with unemployment rising in lockstep with the population explosion, called the attack a "sinful terrorist action."

The attacks came just one day after Al Qaeda leader Usama bin Laden had urged Muslims to support Al Qaeda in what he called a war against Islam.

Egyptian officials have said local people were behind the previous bombings in the Sinai, but outside security experts say Sinai's extremists seem either Al Qaeda linked or at least aligned with its views.

Security officials, who refused to be identified because they were not authorized to release the information, said the remains of three men recovered from the scene of the blasts were so badly torn apart that they could have been suicide attackers.

Arabs throughout the Middle East voiced outrage, signaling a growing backlash as fellow Muslims increasingly bear the brunt of terrorist attacks. Of the 24 dead in Dahab, 21 were Egyptians.

"I don't think these people care" if Muslims or Arabs are killed. "They'll carry on at any price," said Lara Darwazah, a 31-year-old music teacher in Dubai, United Arab Emirates.

All three Sinai bombings were timed to Egyptian national holidays when resorts were especially crowded with local tourists as well as foreigners who flock to the seaside towns, the world-renowned beaches and extraordinary reefs.

Taba and Ras Shitan in the northern Sinai near the Israeli border were hit and 34 killed in October 2004, a day before the holiday marking the start of the 1973 Arab-Israeli war.

Last July 23 -- Egypt's national day -- suicide bombers killed 64 people, mainly tourists, in Sharm el-Sheik on the southern tip of the Sinai.

Monday's Dahab bombings occurred on the eve of Sinai Liberation Day, when Egypt regained full control of the peninsula from Israel in 1986. The tourist population was swollen further by the coincidence of the long Coptic Christian Easter weekend and an ancient Egyptian holiday to mark the start of spring.

Egypt's Sinai resorts are a tempting and virtually made-to-order target for Islamic militants who were jailed by Mubarak or fled to safer territory and became even more radical-- witness Egyptian physician Ayman Al-Zawahiri's migration to Afghanistan and the No. 2 place in Al Qaeda.

The isolated and desolate peninsula also has become a favored Israeli holiday destination, making bombings there both a symbolic attack on Israelis and an assault to undermine Mubarak's authority and rattle his tenuous economy.

Interior Minister Habib el-Adly said it was not immediately clear if the attack could have been carried out by a group as organized as those who detonated the earlier bombs. He said the explosives were different than those used in Sharm el-Sheik or Taba.

The blasts were so powerful that police divers worked Tuesday to retrieve body parts from the shallow waters of the sea, as workers swept shards of glass from the streets. At one spot near the beach, two black sandals lay in a pool of blood on a wooden footbridge.

Nearby, outside the supermarket where one blast occurred, a tiny shoe covered in blood lay on top of a baby stroller. Witnesses said the stroller belonged to foreign twin infants who they said looked European.

One twin was inside the shop with the mother when the blast occurred, and the other outside in the stroller, said Mohammed Emad, 16, who sells spices at the market and whose hand was hurt by flying glass.

The boy said he went with the mother and twins to hospital, where one of the twins died. "I pushed the stroller away out of the doorway" after the blast, he said.

El-Adly put the death toll at 23, including 20 Egyptians and three foreigners. But Sinai hospital officials said Tuesday that an Egyptian man had died of his wounds, bringing the toll to 24. The German Foreign Ministry said a 10-year-old German boy was among the dead.

Dr. Hazem Ahmed of Sharm el-Sheik Hospital said 85 people were wounded.

The World Economic Forum said it would go ahead with plans to hold a meeting of Middle Eastern government and business leaders in Sharm-el-Sheik on May 20-22.

"For the sake of a more peaceful future for humankind we have to show our solidarity by holding this meeting," said Klaus Schwab, the Geneva-based convener of the forum, in a letter to Mubarak.

The Dahab attack seemed consistent with the aims of hardline Al Qaeda sympathizers, often called Salafists.

In contrast, groups like Hamas have been careful to say that their attacks are aimed only against Israel, and are not part of a worldwide radical Islamic jihad.