The knife-wielding suspect killed in Paris on Thursday as he attempted to enter a police station has been named as Sallah Ali, a convicted thief, BBC reported. The suspect was wearing a fake suicide vest as he apparently attempted to carry out an attack.

Ali, 20, was from Casablanca, Morocco, and was said to be carrying a piece of paper with the Islamic State group’s flag. That finding turned the investigation from an individual assault to what was likely an attempted terrorist attack, the Local reported. Investigators said they were exploring links to “terrorist undertaking,” but did not provide further detail, according to the Washington Post.

Investigators said they did not believe other individuals were involved in the apparent attempted attack at the police station. The attack was believed to be in retribution for French airstrikes in Syria, the French newspaper L’Express reported.

France has intensified an airstrike campaign against the Islamic State group, aka ISIS, in Syria since attacks in Paris late last month left some 130 people dead and hundreds more wounded. ISIS claimed responsibility for those attacks and videos emerged of ISIS fighters smiling and handing out candy in celebration. 

The attacker Thursday was believed to have cried out, “Allahu Akbar,” before carrying out the attack. The term means “God is great” in Arabic and has become a routine cry for Muslim extremists before staging attacks. The phrase, however, is commonly used by Muslims worldwide and is not an indicator of extremism.

Thursday marked the anniversary of the Charlie Hebdo attacks, when gunmen killed 17 people at the satirical magazine's offices and a Jewish supermarket. The attack Thursday occurred almost exactly a year later. French President François Hollande paid tribute to France’s emergency services shortly before Thursday’s attack.

"You protect the French people, you also protect their way of life, their freedom,” Hollande said, according to the Washington Post. “This way of life, that’s what the terrorists wanted to attack. Because joy, sharing, culture inspire hatred in them. Never, undoubtedly for decades, has your mission been more necessary.”