Last Updated 11:20 a.m. ET
(CBS/AP) PARIS - French President Nicolas Sarkozy's spy chief says a gunman who killed three young children and a rabbi at a Jewish school only attacked the school after missing his original target a French soldier.
Ange Mancini, Sarkozy's intelligence adviser, said on French TV that Mohamed Merah had wanted to kill a soldier he had targeted Monday in Toulouse, but arrived too late and instead besieged a nearby Jewish school.
Mancini told France-24 TV on Friday that "it wasn't the school that he wanted to attack," calling school shooting "opportunistic."
Merah, a 23-year-old Frenchman of Algerian descent, was killed Thursday in a shootout after police raided the Toulouse apartment where he had been holed up for 32 hours in a standoff with authorities.
Also today, a senior official who is close to the investigation into Merah's attacks told The Associated Press there was no sign Merah had "trained or been in contact with organized groups or jihadists" such as al Qaeda.
The official said Merah might have made the claim because al Qaeda is a well-known "brand." The official said authorities have "absolutely no element allowing us to believe that he was commissioned by al Qaeda to carry out these attacks."
The official spoke on condition of anonymity because of the sensitivity of the investigation.
Merah was killed in a dramatic gunfight with police Thursday after a 32-hour standoff with police. Prosecutors said he filmed himself carrying out three attacks beginning March 11, killing three Jewish schoolchildren, a rabbi and three French paratroopers with close-range shots to the head. Another Jewish student and another paratrooper were wounded.
Meanwhile, inhabitants evacuated from the apartment building when the siege began have been told they can go home tonight, reports CBS News correspondent Elaine Cobbe.
Merah had traveled to Afghanistan and Pakistan, and prosecutors said he had claimed contacts with al Qaeda and to have trained in the Pakistan militant stronghold of Waziristan.
He had been on a U.S. no-fly list since 2010.
France's prime minister and other senior figures have been fending off suggestions that anti-terrorism authorities fell down on the job in monitoring 23-year-old Mohamed Merah, who had been known to them for years.
French Prime Minister Francois Fillon told RTL radio Friday that authorities "at no moment" suspected Merah would be dangerous despite his long record of crime and his time in prison.
"The fact of belonging to a Salafist (ultraconservative Muslim) organization is not unto itself a crime. We must not mix religious fundamentalism and terrorism, even if naturally we well know the links that unite the two," Fillon said.
A little-known jihadist group claimed responsibility for one of the killings. The SITE Intelligence Group, which monitors Internet messages, said Jund al-Khilafah, based in Kazakhstan, issued a statement saying "Yusuf of France" led an attack Monday, the day of the Jewish school shootings.
A French official said the claim appeared opportunistic and that authorities think Merah had never heard of the group.
Investigators looking for possible accomplices decided Friday to keep Merah's older brother, his mother and the brother's girlfriend in custody for another day for further questioning, the Paris prosecutor's office said.
The head of the DCRI intelligence agency was quoted in the Le Monde newspaper as saying there was little sign that Merah's family was involved. Bernard Squarcini said Merah told police that he didn't trust his brother or mother.
Police also said his mother declined to get involved in police negotiations Wednesday with her son, saying she had no influence over him.
Merah was questioned by French intelligence officers last November after his second trip to Afghanistan, and was cooperative and provided a USB key with tourist-like photos of his trip, the senior official said.
The official said when Merah was under surveillance last year, he was not seen contacting any radicals and went to nightclubs, not mosques.
Merah told negotiators during the police standoff this week that he was able to buy an impressive arsenal of weapons thanks to years of being involved in petty theft, the official said.
The picture painted by the official and the chief of the DCRI intelligence agency was of a self-radicalized young man with signs of a split personality.
For years, intelligence services have worried most of all about lone-wolf terrorist who radicalize alone and operate below the radar. Merah told police during this week's standoff that he was trained "by a single person" when he was in Waziristan, Squarcini was quoted as saying in Le Monde.
"Not in training centers, where he could have been singled out because he spoke French," Squarcini was quoted as saying.
According to prosecutors, Merah had told negotiators he went on his rampage to avenge the deaths of Palestinian children and protest the French army's involvement in Afghanistan as well as France's law against the Islamic face veil.
President Nicolas Sarkozy immediately proposed sweeping new anti-terror laws; and National Front candidate Marine le Pen was quick to criticize the government for ignoring the Islamic threat.
Socialist candidate Francois Hollande promised, if elected, to hunt down all terrorists.
Some politicians, French media and Toulouse residents questioned why authorities didn't stop Merah before he started his killing spree.
Families of the victims expressed frustration that Merah was not taken alive.
"Imad's parents feel that the justice they were expecting was stolen from them," said lawyer Mehana Mouhou, lawyer for the family of the first paratrooper killed, Imad Ibn-Ziaten. "His mother wanted an answer to the question, 'why did he kill my son?"'
Cathy Fontaine, 43, who runs a beauty salon down the street from the building in Toulouse where Merah was killed, said France should have a "zero tolerance" policy for people who seek out training in Afghanistan and perhaps even refuse to let them back in.
"An individual who goes to be trained in Afghanistan, you have to follow him," she said.
The chief of the elite RAID police unit, which conducted the raid, told French media on Friday that he was probably killed by a sniper.
"We tried to exhaust him all night before retaking the apartment," Amaury de Hauteclocque was quoted as saying by Le Monde. His commandos slipped into the apartment but Merah was waiting for them, standing in 30 centimeters (a foot) of water after a pipe burst when it was pierced by a bullet during the first assault, the report said.
"I'd given the order to only fire back with stun grenades. But as he moved through the apartment he tried to kill my men who were on the balcony. It's probably one of the snipers that got him," he said.
He said on RTL radio that 15 men had taken part in the assault, which took about an hour as police slowly penetrated Merah's apartment. He described the apartment like "a battle zone," with furniture piled up as a barricade.
He said if it had been a case of nabbing Merah "dead or alive," the police would have stormed his apartment immediately instead of waiting 32 hours.
"If we have four injured among my men, it's because we tried until the end to get him alive," he said.