Hayat Boumeddiene, 26, left France on Jan. 2 and entered Syria from Turkey on Jan. 8, according to the source.
Boumeddiene is wanted by police after being linked to suspected gunman Amedy Coulibaly, who is suspected of killing a policewoman and four hostages at kosher market Friday.
Coulibaly was killed after police stormed the market.
French police suspect she served as the communication link between Coulibaly and the other members of the terror cell behind the massacre that killed 12 people at the Charlie Hebdo newspaper offices, the brothers Cherif and Said Kouachi. The two brothers were killed Friday when police stormed the printing press where they'd holed up.
A French police source with close knowledge of the case told ABC News that Hayat Boumeddiene traveled from Paris well before the attacks started on Jan. 7 with the shooting rampage at Charlie Hebdo.
She reportedly first arrivied in Madrid on Jan. 2 and then traveled to Istanbul and then left for Syria by Jan. 8, which is the same day Coulibaly is suspected of killing the police woman.
According to a U.S. senior intelligence official, the Charlie Hebdo attackers had support in the plot from an unknown number of "enablers" in some form of jihadi support network that reached into both Syria and Yemen.
Also still being investigated is the question of whether the jihadi gunmen in Paris were trained and directed by al Qaeda in the Arabian Peninsula or other terror group, or whether there was terror training by AQAP before they hatched a self-directed plot.
Police are trying to decipher what role Boumeddiene played in the attacks as they search for her. She and Coulibaly had been married in a religious ceremony in 2009, but never made it official with a French civil ceremony.
According to the Paris Public Prosecutor's office, Boumeddiene had spent the last year in contact with the wife of one of the gunmen believed responsible for the Charlie Hebdo massacre.
She had exchanged 500 phone calls with the wife of Cherif Kouachi, one of the suspected Charlie Hebdo gunmen, according to the prosecutor's office.
In 2010 Boumeddiene was questioned by French police and asked about her reaction to al Qaeda terrorist acts.
"I don't have any opinion," she answered, according to The Associated Press report from her judicial records.
However, she also said that Americans were killing innocent people who needed protection, and said she was suspicious of the media's reports, according to the AP.
Around the time she was married she started wearing full Islamic veils, which led to losing her job as a cashier, she told interrogators, according to the AP.