See face of 1 of the killers in Paris attacks

Multiple attacks in Paris, France on the night of Friday 13th of November, has left over 150 people dead and even more injured.

Investigations have revealed that one of the seven terrorists suspected of perpetrating the terrorist attacks was travelling with a Syrian passport.

READ: Syrian President blames French foreign policy for attacks

The suspect has been identified as 25-year-old Ahmad Al-Muhammad.

According to Reuters, the suspect probably arrived in Europe through Greece, citing government sources.

The deputy head of the Greek Ministry of Interior, Nikos Toskas, said Friday that one of the suspect got into Greece by October, "escaped as an immigrant on the island of Leros in the Dodecanese Islands in the Aegean Sea and "was there identified in accordance with the principles of the EU."

According to Blic, he then entered Serbia on October 7 at Miratovce, from Macedonia. It is believed according to Syrian authorities that he wasn't armed while crossing through Serbia.

He arrived in Presevo, where he formally applied for asylum. He then continued his journey and, as Blic learned, quickly left Serbia and went to Croatia and further to Austria.

His next precise stop was France.

French President Francois Hollande has condemned the attacks, calling it an act of war on French values and declaring that merciless retaliation will follow.