The ringleader of an Islamic terror group, who spearheaded a plot to blow up a railway station in Germany has been sentenced to life in prison.

Marco G., 29, was caged at Duesseldorf Higher State Court on Monday for the plot which, had it succeeded, would have caused a bloodbath at Bonn main station.

His two accomplices were served jail terms between nine-and-a-half to 12 years for the planned bombing and a later scheme to kill a far-right politician.

The defendant Marco G. seen sitting in the courtroom of the Higher Regional Court in Duesseldorf, Germany, in September 2014 - he has now been sentenced to life in prison

A handout picture shows the bag which contained the bomb that was placed at Platform One of Bonn central station in Cologne, Germany, on December 12 2012

The defendants have sat for nearly four years on remand in jail as prosecutors built their case against them.

On December 10 2012 a DIY bomb was discovered on Platform One at the train station in what was once the capital of former West Germany.

Tucked into a blue bag and pushed under a seat was the pipe bomb rigged up to a timer made from an alarm clock.

A defect in the contraption's construction prevented its detonation.

The defendants have sat for nearly four years on remand in jail as prosecutors built their case against them

DNA on the bomb bag led detectives to the home of German born Muslim convert Marco G., pictured above at the Higher Regional Court in Duesseldorf

DNA on the bag led detectives to the home of German-born Muslim convert, Marco G.

They found explosives in his fridge and an Al-Qaeda bomb-making manual in his bedroom.

Prosecutors described Marco G. as 'enemy of the state' number one and had him flown by helicopter in handcuffs every day of the trial after plans for a breakout were discovered in his cell.

After the failed bomb plot, in 2013 the Salafist group planned to kill a far-right politician. That too failed.

A video sequence shows the blue bag containing a bomb being carried through Bonn central train station on December 12 2012

The bomb scare caused severe delays to the rail network and police scoured the site

The pipe bomb had been tucked under a train seat and it was rigged up to a timer made from an alarm clock. A defect in the contraption's construction prevented its detonation.

'Both acts were plotted to take revenge on people who criticised the prophet Mohammed. They wanted to kill many people,' said federal prosecutor Horst Salzmann.

Marco G.'s friend Enea B., 44, a former special forces soldier with the Albanian military, was assigned to assassinate Markus Beisicht, leader of the far-right PRO-NRW party for promoting anti-Muslim sentiments with slogans like 'Freedom not Islam'.

The murder bid failed because Beisicht was not at home in his apartment in Leverkusen at the time.