A Pakistani extremist linked to the 2008 Mumbai terror attacks has reportedly been arrested in Austria on suspicion of planning attacks in Europe.

The suspect is one of two men arrested in Salzburg posing as refugees on suspicion of planning attacks for Islamic State in Iraq and the Levant (Isil). The 34-year-old man, who has not previously been identified, was named as Muhammad Ghani Usman by the Sunday Times.

He is said to be a former bombmaker for Lashkar-e Taiba (LeT), the Pakistani group behind the 2008 attacks in Mumbai, in which 164 people were killed.

Unnamed sources close to a multinational investigation said “dozens” of Isil operatives entered Europe posing as asylum-seekers and are still at large.

Austrian prosecutors have confirmed that two men arrested on December 10 in Salzburg entered Europe posing as Syrian refugees last October. They arrived in Greece on the same boat as two of those involved in last November’s Paris attacks.

The second man was named as Adel Haddadi, a 28-year-old Algerian, and claimed investigators believe they were members of one of a number of Isil “strike teams” who infiltrated Europe under cover of the migrant crisis.