"During our investigation we found that between December 2014 and September 2016 Mourad T. was involved with an armed crime organisation -- an international terrorist organisation called Islamic State," prosecutors said in a statement.
This marks the first Polish investigation of an Islamic State member, which the domestic counter-intelligence agency ABW undertook after receiving information from its EU counterparts.
According to local media, the first intel came from the CIA.
Prosecutors added that Mourad T. was an "accomplice" and "scout" for Abaaoud, who planned the November 2015 attacks in Paris that killed 130 people.
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Mourad T. notably met with Abaaoud in the Turkish city of Edirne in late 2014, along with Sofiane Amghar and Khalid Ben Larbi, two jihadists who were killed in a terror raid in Belgium in 2015.
Mourad T. used false identities and spent time in several EU countries as well as in Turkey and Serbia.
Prosecutors added that they found instructions on how to make explosive devices and photos of potential targets on his telephone.
In December 2014, he left Turkey "along with other people engaged in terrorist activity" planning to go to Germany.
Instead, he entered Greece illegally, passed through Macedonia and Serbia before reaching Hungary. From there, he entered Austria, then the Czech Republic and finally Poland.
He arrived in Austria in February 2015 and requested a permanent residence permit, which he later used in Vienna and Poland, where he was found in possession of small amounts of hashish, marijuana and MDMA tablets.