Egypt sacked its two security chiefs for the Sinai peninsula after the Saturday bombings in their region. The Health Ministry said 64 people were killed but local hospitals put the toll at 88, saying the ministry count does not include sets of body parts.
Early Monday morning, police launched a sweep in a desert mountain area about 24 miles from Sharm's main strip of hotels after they got a tip that several unidentified men were seen fleeing in that direction, security officials said.
Police at checkpoints around this resort also were circulating photographs of five Pakistanis who apparently were among a group of nine Pakistanis who arrived in Sharm el-Sheik from Cairo on July 5, according to two investigators who spoke on condition of anonymity because of the probe's sensitivity.
The five were identified as Mohammed Anwar, 30; Rashid Ali, 26; Mohammed Aref, 26; Musaddeq Hussein, 18; and Mohammed Akhtar, 30. The pictures, which gave the men's names and passport numbers, also were on posters put up in Cairo, apparently out of concern they were in the capital either before or since the attacks.
But officials did not say the men were known to be connected to the bombing. One senior official said the men had overstayed their visas and police were looking widely into any illegal activity in the wake of the blasts.
If any involvement of Pakistanis is confirmed, it would suggest that those behind Saturday's bombings belong to a much wider terror network than previously believed.
Terrorism expert Jessica Stern told CBS News' The Early Show she would not be surprised if Pakistani terror groups were involved.
"I think that we know that for a long time Pakistani jihad groups have been working together with Egyptian groups as part of the international Islamic front," says Stern, author of "Terror in the Name of God,"
"So, even though it's unclear who is responsible, it would not be surprising if there's responsibility from both camps."
President BushMonday at the Egyptian Embassy in Washington and said the people responsible for the deadly attack "have no heart."
Mr. Bush said his visit was meant to "reiterate my country's strong desire to stand shoulder-to-shoulder with the people of Egypt and bring justice to those who killed innocent people."
Egyptian security forces already have detained more than 70 people in Sharm and other parts of the Sinai since the attacks.
On Sunday, police said they were hunting for three bombers who may have escaped after the attack. They said a fourth attacker apparently was a suicide bomber who crashed a pickup truck laden with explosives hidden under vegetables into a hotel lobby.
Another avenue investigators have been following is that Saturday's attacks were carried out by a Sinai-based network believed responsible for the October bombings in the Sinai tourist resorts of Taba and Ras Shitan, about 125 miles north of Sharm el-Sheik. Those attacks killed 34 people.