Armed police are continuing to surround an apartment building in the French city of Toulouse where a man suspected of killing seven people is believed to be engaged in an armed standoff.
But Claude Gueant, the French interior minister, told French radio on Thursday that there had been no movement at the apartment overnight and police could not be certain that the suspect was still alive.
"Despite renewed efforts all through the night to re-establish contact by voice and radio, there has been no contact, no showing from him," said Gueant.
More loud explosions again shook the neighbourhood on Thursday, following similar blasts late on Wednesday in what the French interior ministry said were efforts to intimidate the suspect, named by police as Mohamed Merah, who has reportedly claimed responsibility for the killings of French soldiers, a rabbi and three children.
The suspect is thought to be armed with an assault rifle, a submachine pistol and a collection of handguns, and ministry officials said there had been no attempt so far to confront or detain him.
Rain poured down on police, firemen, media and around a dozen bystanders who spent the night outside the apartment.
Al Jazeera's Jacky Rowland, reporting from Toulouse, said the use of explosives appeared to have been an effort to put the suspect under added psychological pressure intended to convince him to surrender himself.
"The police and authorities want to deprive him of sleep and put him under much stress as possible so he'll surrender or they can move in," our correspondent said.
"They want him alive, they want to put him on trial; also they want to question him on whether he has any others associates."
Francois Molins, France's top anti-terrorism prosecutor, said on Wednesday that the gunman had been planning another attack, prompting a major police raid on his apartment.
"He has no regrets, except not having more time to kill more people. And he boasts that he has brought France to its knees," Molins, part of the anti-terrorist unit leading the investigation, told a news conference.
French religious leaders join together in wake of killings
French President Nicolas Sarkozy who is running for re-election in five weeks time, has paid homage to the soldiers killed by the gunman. He said that the three French soldiers killed last week were victims of a "terrorist execution".
Speaking at a memorial service for the soldiers in Montauban, Sarkozy said that "terrorism will not break [the] country, and the country must not give in to revenge".
Sarkozy, who also visited the scene of the siege, said the killer had wanted to "bring France to its knees", but had failed, and said the attacker would likewise fail in his attempt to divide the country.
Speaking to journalists, Gueant said the suspect was a French citizen with links to al-Qaeda.
He said the suspect wanted to "take revenge for Palestinian children" killed in the Middle East, and was angry at the French military for its operations abroad.
Michael Stephens, a researcher with the Royal United Services Institute in Qatar, however, told Al Jazeera the interior minister needed to step back until there was more evidence.
"There is very little evidence of organisational structure behind the attack. It is more likely he was acting alone and radicalised by al-Qaeda ideas," he said.
| The funerals of the rabbi and three children killed on Monday have been held in Jerusalem [REUTERS]
Gueant further added that the man's brother was arrested and that he was known to authorities for having spent time in Afghanistan and Pakistan.
The raid came as three Jewish children and a rabbi killed outside the Ozar Hatorah school in Toulouse were buried in Israel.
Jonathan Sandler, a 30-year-old Frenchman, his two sons, five-year-old Arieh and four-year-old Gabriel, as well as seven-year-old Myriam Monsonego, were buried at the Givat Shaul cemetery in Jerusalem.
French police on Monday launched a huge manhunt after the school shootings, and the Midi-Pyrenees region was put on its highest level of security alert.
Police said that the same weapon and the same stolen scooter appeared to have been used in both the school attack and two other attacks that left three soldiers dead.
All seven people slain in three attacks were shot in the head at point blank range, the prosecutor leading the investigation said on Tuesday.