An ISIS fighter from Germany who was arrested when he returned says his fanatical commanders tried to recruit him to carry out atrocities in his homeland.

The man, known only as Harry S, said many of the 750 ISIS volunteers from Germany are being asked to fly back to target Germany in the same was as Paris.

The security services have long warned that the country is ripe for a revenge terror attack for its support of coalition efforts against ISIS.

When he was in Syria, Harry S, 27, from Bremen, was also asked to take part in the execution of prisoners but claims he did not.

Harry S (pictured, from his Instagram account), who returned to Germany after joining ISIS in Syria, says the group tried to convince European jihadis to wage Paris style attacks in their home countries

The German jihadi said many of the 750 ISIS volunteers from Germany are being asked to fly back to target the country in the same was as Paris (pictured, the aftermath of the Bataclan theatre massacre)

He is now in investigative custody pending a trial for membership of a terrorist organization and his lawyer says he wants to 'come clean.'

He travelled to join ISIS in Syria in 2014 but left just three months later after becoming disillusioned with life under the terror group's rule. He left by walking all the way back to Turkey.

Harry S told of how ISIS commanders tried to recruit volunteers for terror attacks in Germany, said German newspaper Spiegel after visiting him in prison

Another Islamist from Bremen, north west Germany, was approached to carry out such an atrocity, he said.

He said ISIS fighters propositioned 'pretty much every European' fanatic in its de facto capital Raqqa to return home to carry out an attack.

The returned jihadi converted to Islam while serving time for a supermarket robbery.

Shortly after his release from prison, he was drawn to the religion's dark side and he became part of a clique supporting jihad - or 'holy war' against the West.

A large man with broad shoulders, Harry S was trained as an ISIS fighter in Syria, Spiegel reported.

Harry S spent time with Austrian fanatic Mohamed Mahmoud and Berlin rapper Denis Cuspert (pictured) - known as Deso Dogg - while in Syria

Home grown jihadi: Harry S travelled to join ISIS (file photo) in Syria in 2014 but left just three months later after becoming disillusioned with life under the terror group's rule

He claimed to have been trained at the terror group's army camps with 50 other men who were forced to stand for hours in the sun and made to do marches that lasted the entire day.

He said anyone who gave up was brutally beaten by their commanders.

Once he 'graduated' from training, Harry S claims he joined a special unit but was never actually sent into battle.

He spent time with Austrian fanatic Mohamed Mahmoud and Berlin rapper Denis Cuspert - known as Deso Dogg - while in Syria. Both are thought to have been killed in coalition airstrikes.

Cuspert became the Joseph Goebbels of the movement, producing their grisly beheading videos using film editing skills he learned back in his rapping days.

Harry S made it back to Germany with video images on his mobile phone of the executions of ISIS captives.