French authorities raced Saturday to find the girlfriend of one of three dead Islamist suspects, who authorities declared was "armed and dangerous" and heavily involved in the terrorist attacks that rocked France for three days.
But as the whereabouts of Hayat Boumeddiene proved elusive, it appeared she may have traveled to Syria days before the attacks, sources told French news media and the Associated Press.
An unnamed Turkish intelligence official told AP on Saturday that a woman by the same name flew from Madrid to Istanbul, Turkey, on Jan. 2, five days before Wednesday's massacre at the office of the satirical magazine Charlie Hebdo, and from there may have crossed the border into Syria.
The official said that the woman resembled a widely distributed photo of Boumeddiene and that she was believed to have traveled to the Turkish city of Sanliurfa, near the Syrian border, where "she then disappeared."
She had a return flight booked for Jan. 9 that she did not take, according to French news sources.
Boumeddiene, 26, was suspected of serving as an accomplice to her partner, Amedy Coulibaly, who took more than 15 people hostage at a Paris grocery store Friday, killing four of them.
Authorities thought she may also have also helped Coulibaly gun down a Paris policewoman on Thursday.
Details emerged Saturday of a woman who went from posing in a bikini on a beach to wearing black Islamic garments, with only her eyes showing.
She reportedly grew up in a family of seven children in the Paris suburb of Villiers-sur-Marne, and her mother died when she was 6. He father was unable to look after his family while also holding down a full-time job, according to French news reports, and she may have ended up in foster care.
Reports suggest she became radicalized during her relationship with Coulibaly.
Images published in Le Monde newspaper showed Boumeddiene covered head to toe, menacingly pointing a crossbow at the camera.
She and Coulibaly, the reports said, also spent time with Djamel Beghal, who was imprisoned for planning an attack on the U.S. Embassy in Paris in 2001.
As news about Boumeddiene and the slain gunmen trickled out, Paris geared up for a massive solidarity rally Sunday, which is expected to attract hundreds of thousands.
Those scheduled to attend include British Prime Minister David Cameron, Palestinian Authority President Mahmoud Abbas and Israeli Prime Minister Benjamin Netanyahu.
Security was being bolstered for the march, and French Interior Minister Bernard Cazeneuve said, "All the measures are in place to make sure this event takes place securely."
The bloodiest episode in recent French history left 17 victims dead and several injured, and panicked a nation now struggling with the question of how to handle homegrown Muslim extremists.
The carnage began Wednesday morning, when Said and Cherif Kouachi entered the Charlie Hebdo offices in central Paris and killed 12 people, including eight journalists and two police officers, authorities say.
The brothers then went on the run and were finally cornered Friday in a printing factory in the town of Dammartin-en-Goele, about 30 miles northeast of Paris near Charles de Gaulle Airport.
While attention was focused on that police operation, Coulibaly entered a kosher grocery store in east Paris, taking hostages. He is also believed to have shot and killed a female police officer investigating a report of a traffic accident in the south of Paris on Thursday morning.
The two tense standoffs ended nearly simultaneously, with all three suspects dead and Boumeddiene's whereabouts unknown.
As police stormed the grocery where Coulibaly was holed up, the Kouachi brothers exited their hide-out and opened fire on officers, who had them surrounded, authorities said. The siblings had also taken a hostage, but he was released unharmed and, unbeknownst to them, a second man had been hiding out in a second-floor office. That man, who fed vital information to police via cellphone, also emerged safely.
Authorities believe there were close ties between the Kouachi brothers and Coulibaly and Boumeddiene.
Coulibaly had reportedly telephoned BFM TV in the afternoon and, when asked whether there was a link between him and the Kouachi brothers, he responded, "Yes, we synchronized ourselves for that, the operations."
Paris' chief prosecutor, Francois Molins, also said that Boumeddiene was in "constant and sustained" communication with the romantic partner of Cherif Kouachi.
"More than 500 calls" were made between the two women last year, he said, according to French news reports.
French President Francois Hollande called an emergency Cabinet meeting Saturday, and Cazeneuve announced the deployment of an extra 320 military personnel.
The Interior minister urged the nation to remain alert. "We are exposed to risks," he said.
Prime Minister Manuel Valls gave a long and impassioned speech Saturday praising security personnel for their work, and spoke about the terrorists' desire to divide the nation and "attack symbols of France."
"The best response is national unity," he said.
Valls said the attackers deliberately took aim at journalists because they represent freedom of expression, the police who seek to protect the public, and also the Jewish community.
"They wanted to annihilate a newspaper, Charlie Hebdo, that must live on," he said.
But he also warned that the threat of another extremist attack remained very real and vigilance was needed. "We must not let our guard down."
Many questions remain unanswered, including how the three men were able to get their hands on such an array of weaponry, including Kalashnikov and other assault rifles, and why they were not under closer watch when they were already known to authorities who monitor security threats.
The Kouachi brothers were on a U.S. no-fly list, and Said, 34, had been trained in weapons handling in 2011 by Al Qaeda in the Arabian Peninsula, American officials said.
Cherif Kouachi, 32, was convicted of terrorism-related charges in France in 2008 for recruiting insurgents to fight against U.S. forces in Iraq. He served 18 months, and authorities declined to prosecute him in a separate case involving a plot to free a fellow militant from prison.
Events took place across France on Saturday to commemorate the attacks, and makeshift memorials sprang up around Paris. Residents flocked to the Charlie Hebdo offices and the grocery to lay flowers, light candles and pay their respects to the victims.
The streets were noticeably calmer, but there were still signs of frayed nerves. Police briefly shut a section of road near the Place de la Bastille in the afternoon after a report of a suspicious package. It was a false alarm.
Near the Charlie Hebdo offices, a makeshift memorial to the victims had swelled into a mountain of flowers, candles, handwritten messages and pens — an instrument that has come to symbolize defiance against the attackers. A steady stream of people filtered past quietly while a young man in the corner played Bach on a cello.
"I felt the need to express myself and pay tribute to the Charlie Hebdo victims," said Gilles Van Elslande, 27, who said this was the first time he had played in public. "I think the cello is very sentimental. This is the right time to play Bach."