Many aspects of the investigation were shrouded in mystery on Tuesday, three days after the blasts, with no clear direction emerging so far, contradictory information on the casualty toll and three claims for the attacks.
Security sources said investigators suspected that a known Sinai Islamist called Yusef Badran was one of the bombers involved in the triple bomb attacks in the Red Sea resort on Saturday.
DNA tests were being carried out on his family and compared with the remains of the suspected Ghazala Gardens hotel bomber, the most devastating of the strikes.
Badran had been suspected of involvement in another wave of attacks that killed 34 people in the Sinai resorts of Taba and Nuwaiba farther north in October.
His family in the Sinai town of al-Arish said he had been missing for months.
"He was arrested after the Taba bombings and later released," his mother-in-law, Mariam al-Sawarta, said. "But I know nothing about his situation. He got married and lived in a village called al-Metni, south of al-Arish."
A tourist takes pictures of a car
damaged in Saturday's blasts
Egyptian forces have been combing the Sinai since Saturday's bombings, arresting about 200 people.
Interior Minister Habib al-Adly said as early as Saturday there could be links between the Sharm al-Shaikh bombings and the anti-Israeli attacks in Taba.
Officials denied the involvement of any Pakistani nationals in the Sharm al-Shaikh bombings.
In a twist that heightened fears of a new wave of coordinated global al-Qaida-linked terror attacks after the 7 July attacks in London, Egyptian security sources had said on Monday that six Pakistanis who entered the country this month were being sought over the Sharm al-Shaikh bombings.
Their pictures were among those of dozens of suspects posted in police stations in the Sharm al-Shaikh area and in Cairo.
Egypt's ambassador to Pakistan Hussein Haridy said he had informed Islamabad "that no Pakistani national was involved in the terrorist acts that rocked Sharm al-Shaikh late last Saturday".
Adly's first adviser, Mohammed Sharawi, said that the six Pakistanis were not linked to the bombings and that security services never distributed the pictures.
"It seems the government has no serious leads and it cannot conceal its unease," said Dhiaa Rashwan, from the Al-Ahram Centre for Strategic Studies.
Three days after the bombs ripped through the glitzy beach and dive resort, a question remained about the toll, with the health and tourism ministries saying 67 people had perished.
"The death toll stands at 67, among them 16 foreigners," Tourism Ministry spokeswoman Hala al-Khatib said on Tuesday. Hospital officials have previously said that 88 died.
"It seems the government has no serious leads and it cannot conceal its unease".
Al-Ahram Centre for Strategic Studies
Al-Khatib refused to give the breakdown of nationalities, but reports suggested Italians, Turks and Britons are among the foreign dead, whose number is expected to rise.
Revenge and response
A previously unknown movement calling itself the Unity and Jihad Group in Egypt said it perpetrated the attacks "in revenge for our brothers in Iraq and Afghanistan... and in response to the war against terror".
"It was also out of loyalty to the leaders of the mujahedeen within the Al-Qaeda network, Shaikh Osama bin Laden and Sheikh Ayman al-Zawahiri, may God preserve them," said the statement, whose authenticity could not be verified.
The group said it also carried out the October bombings. It named five "martyrs" it said died in the Sharm al-Shaikh attacks. The names differed from those given by another group that claimed responsibility for the bombings on Monday, Mujahedeen Egypt.
The first group to claim responsibility for the attacks, the deadliest in Egypt, was a movement calling itself the al-Qaida Organization in the Levant and Egypt.
Sharm al-Shaikh was crowded with tourists when the pre-dawn bombs went off and foreign embassy officials were still in the resort on Tuesday.
Police said about 600kg of explosives were used in the attacks that destroyed the Ghazala hotel and struck a car park and a busy market area.
South Sinai Governor Mustafa Afifi said a temporary checkpoint set up near the souq before the attacks had prevented one of the bombers from reaching a nearby hotel.