Paris ( CNN ) French police have arrested four people linked to Amedy Coulibaly , the gunman and hostage-taker at a Parisian kosher supermarket on January 9 , a Paris prosecutor 's spokesman said . A French policewoman is among the four taken into custody , French national police said . The policewoman worked at the Fort de Rosny-sous-Bois , northeast of Paris , the spokesman said . According to Le Figaro newspaper , the Fort de Rosny-sous-Bois is the location of an important intelligence center . Coulibaly killed four hostages in the grocery store before police shot and killed him . His attack followed one on the office of the French satirical magazine Charlie Hebdo . France has been under a heightened state of alert since January 's terror attacks in Paris that killed 17 people . Brothers Cherif and Said Kouachi , authors of the deadly attack on the Charlie Hebdo offices , were killed days later after two violent standoffs . The brothers were accused of killing 12 people in a massacre at the magazine offices . Coulibaly , suspected in the slaying of a police officer , was killed by security forces after he shot and killed four hostages during the siege at the kosher market . Charlie Hebdo has a controversial history of depicting the Prophet Mohammed , often in an unfavorable light , which has angered many Muslims around the world . Earlier cartoons depicting Mohammed spurred protests and the burning of the magazine 's office three years ago . Since the attack , European nations have carried out raids on suspected terror cells with links to ISIS in Syria .
Four people connected to gunman Amedy Coulibaly have been arrested , official says . The four were taken into custody in the Paris suburb of Montrouge and are being questioned by police about their possible role in a terrorist plot that targeted French satirical magazine Charlie Hebdo last week.