This is the moment video cameras caught the partner of one of the Paris attackers arriving in Turkey, as police continue to search for possible accomplices of the gunmen who carried out last week's terrorist attacks. The video shows Hayat Boumeddiene, now France's most wanted woman, at immigration at Istanbul airport on 2 January, six days before her partner, Amédy Coulibaly, killed a policewoman in Paris. Coulibaly went on to murder four hostages at a kosher supermarket, before being killed in a shootout with police. On Monday the French government said it was clear he had help. In the Istanbul footage, Boumeddiene is accompanied by Mehdi Sabri Belhouchine, a 23-year-old French national whose name had not appeared in connection with the attacks, and who was not on a terrorist watchlist. After crossing Turkey, the pair are said by Turkish authorities to have gone into part of Syria controlled by Islamic State (Isis), to which Coulibaly declared his allegiance before his death. There are some reports that Chérif and Saïd Kouachi, the two gunmen who attacked the Charlie Hebdo offices and killed 12 people on Wednesday, had help. Some witnesses have talked of a third person at the scene of the attack on the magazine. French police officials said as many as six members of the terrorist cell involved in the attacks may still be at large, including a man who was seen driving a car registered to Boumeddiene. Two French police officials told Associated Press that authorities were searching the Paris area for the Mini Cooper registered to Boumeddiene. Officials believe Coulibaly may have had help from accomplices apart from Boumeddiene, with whom he lived in Paris. Someone edited and posted a video of him justifying his actions on Sunday morning, after his death in the shootout on Friday. At least one segment of the video, in which Coulibaly swears allegiance to Isis, was evidently filmed after the wave of attacks began last Wednesday as the noise of news reports can be heard in the background. That was five days after Boumeddiene left France for Turkey. The police are also investigating two further cases that may be linked to the attacks. A 32-year-old man jogging in the southern Paris suburb of Fontenay-aux-Roses on Wednesday was shot with the Tokarev gun later found at the kosher supermarket, the French prosecutor said. Police are also investigating a car explosion - which resulted in no casualties - on Thursday in Villejuif, a town in the southern suburbs of Paris. In the video posted online, Coulibaly claimed he had bombed a car. Turkey's foreign minister said that Boumeddiene had crossed into Syria on Thursday, the day Coulibaly shot dead Clarissa Jean-Philippe, a 27-year-old newly trained policewoman. Turkish media claimed that when Boumeddiene and Belhoucine first entered Turkey, officers of the risk analysis centres, recently established at airports and customs in order to prevent foreign fighters entering Syria and Iraq, found the pair suspicious and started to follow them in Istanbul. They stayed at a hotel in Kadiköy, a district bordering the sea on the Asian side of Istanbul, until 3 January. Witnesses told Turkish reporters that the pair had left the hotel only twice while staying there. Turkish secret intelligence officials said that no information had previously been shared by their French colleagues on either Boumeddiene or Belhoucine, and that they therefore abandoned the investigation of the pair who are not reported to have made contact with anyone else while staying in Istanbul. According to Turkish police the couple's phone signal was picked up on 4 January in Sanliurfa, close to the Syrian border, from where they are thought to have travelled to Akcakale, a crossing point on a stretch of the Syrian border occupied by Isis. It is thought the two French nationals crossed into Syria from Akcakale. The investigation also extends to Yemen, where authorities say the Kouachi brothers were given training in 2011 by al-Qaida in the Arabian Peninsula (Aqap).