Austria is investigating two suspects for possible links to the bombers and gunmen who carried out last year's deadly Paris attacks.

State Prosecutor Robert Holzleitner says they are a 28-year old Algerian and a Pakistani, 32.

He said in a statement Thursday that the two arrived to Greece in the same boat as two of the attackers. He says the attackers were able to leave Greece unhindered but the two now in Austrian investigative custody were held there for 25 days for having fake passports.

Holzleitner says the two were detained in Salzburg Dec. 10. He says a 25-year old Moroccan and an Algerian aged 40 who were in "close contact" with the other two also are being held.

All four are suspected of links to the Islamic State group.