“Leads pointing to this are being looked into,” prosecutors in Salzburg said, adding however that the identity of the Pakistani suspect, who has been in custody since December in the western Austrian city, has not been confirmed.
“Wide-ranging investigations on this question, among others, are ongoing, although the public prosecutors’ office has been waiting for information on this from Pakistan since December 2015,” they said in a statement.
A source in Paris and the Sunday Times said that the man is thought to be a bomb maker for Pakistani extremist organisations Lashkar-e-Taiba and Lashkar-e-Jhangvi.
India holds Lashkar-e-Taiba (LeT), allegedly linked to Al-Qaeda, responsible for the 2008 Mumbai assault that killed 166 people. Lashkar-e-Jhangvi is blamed for a string of high-profile attacks in recent years.
The 34-year-old was arrested in Austria in December along with an Algerian.
French investigators suspect that the Islamic State (IS) group, which claimed responsibility for the Paris bombings as well as attacks in Brussels on March 22, sent both men to Europe to carry out attacks.
Austrian authorities said in February that they are believed to have been in the same boat bringing around 200 migrants to Greece as two men involved in the Paris atrocities.
While those involved in the attacks were able to travel onwards, the pair were held up by Greek authorities for 25 days because they were carrying fake Syrian passports.
They then arrived in Salzburg at the end of November — after the Paris killings — and Austrian police arrested them at a centre for migrants on December 10.
A senior security official in Pakistan told AFP he had no information.
“We are completely in the dark about such a person… who he is, his identity and his affiliations,” the official said.