Cairo  - As the morning light broke on Monday over minarets crowding the 1,500-year-old Cairo neighbourhood where a bomb had killed a French tourist and wounded 21 others the night before, Egyptians tried to make sense of the attack.

Many asked themselves who could have been responsible.

"We cannot really point a finger and say an Iranian or a Jew did it, maybe it is someone from Gaza who wants to tell people, 'wake up,' because these bombings are frequent in places like Gaza and Iraq," said Rifaat al-Sheikh told Deutsche Presse-Agentur dpa on Monday.

The 33-year-old merchant's shop looks out on Hussein Square, the site of the bombing.

Montasser al-Zayat, a lawyer who was once a close associate of deputy al-Qaeda leader Montasser al-Zayat in the Gamaa Islamiya before the two had an acrimonious split and al-Zayat recanted his previous belief in armed struggle against Arab governments, told dpa that he didn't believe the attack had been carried out by any organized group.

"From the primitive nature of the operation, it seems that this was not supported by an organization inside or outside Egypt. The perpetrators were unsophisticated in their bomb-making and tactics," al-Zayat said.

"With the crowds in Hussein, it's very easy to leave something on the ground and walk away, even with all the security," he added.

"It might have been jihadist youths who didn't have affiliations to any group, but were simply affected by what was happening in Gaza and by the Arab's failure to come to Gaza's aide. It's possible these emotions led them on a search for revenge against the world, as embodied by these innocent tourists."

Al-Zayat said that Egyptian security would do better to focus its energy on emerging threats rather than "besieging" Gamaa Islamiya leaders who have recanted their old ideology in exchange for freedom.

"Because security is besieging those who have recanted, they don't have resources to look out for new threats," he said.

Diaa Rashwan an expert on Islamist political groups with Cairo's government-owned al-Ahram Center for Strategic Studies agreed that the perpetrators were likely unsophisticated and operating without connections to outside groups.

"The bombs were locally made and of primitive material. There is no security police in the world that can prevent an operation like this one."

On the streets around the site of Sunday's attack, though, many blamed Israel.

"If a terrorist organization did this, we would have witnessed similar attacks more frequently after the 2005 explosion that struck a market nearby. I think Israel did it this time to harm the Egyptian tourism industry, which is like the blood that moves the country," said Mohsin al-Hindawi, 53, who sells traditional Egyptian robes to tourists.

"No Egyptian Muslim or Christian would do something like this in a sacred place like Hussein Square," he said. "Mark my words, the Israelis are behind it. It takes a lot of dollars to carry out these attacks."

Mustafa al-Hinawi, the 45-year-old owner of a perfume shop nearby, agreed.

"Israel did this because they are passing through a phase of instability and they want to harm Egypt's peace and security by hitting our tourism," he told dpa.

Others in the neighbourhood did not need to look for elaborate explanations.

"The extremists groups did it, just like last time," said Khaled Murshid, 41, who owns an accessory shop in the adjacent Khan al- Khalili bazaar.

Nabil Abdel-Fatah, another analyst from Cairo's al-Ahram Center, said that while it was impossible to know who was behind the attack at this stage, it "might have been an intelligence agency from a country in the region that wants to send a message to Egypt that it can have an impact inside the country."

"It could have been groups influenced by Hamas and Hezbollah, or an Egyptian radical group with a Salafist-jihadist ideology that has become part of the al-Qaeda network. Or it could have been some psychopath," he said.

"But at the end of the day, an attack like this embarrasses the security forces because this should be one of the most highly-secured neighbourhoods in Cairo. Whoever did this meant to recall the attacks of the 1990s," when Egypt battled violent Islamist groups that perpetrated a string of deadly attacks at popular tourist destinations.

"The perpetrators hoped to prove, by means of a simple operation, that there is no stability in Egypt." (dpa)