Mohamed Amra - the escaped French prisoner known as 'The Fly'

Mohamed Amra - the prisoner who escaped from a prison van during an ambush by armed men who killed two prison officers and wounded others - is said to have ties to a gang in the southern city of Marseille, which has been plagued by drug-related gang violence.

Known as "The Fly", Amra was being taken from court to a prison in the city of Rouen near Paris on Tuesday when a car rammed the prison van at a toll booth and armed men opened fire.

Prosecutors say the 30-year-old had been convicted of burglary on 10 May and had also been indicted by prosecutors in Marseille for a kidnapping that led to a death.

He was being held at the Val de Reuil prison, near Rouen, and had reportedly appeared at a nearby court in relation to those new charges prior to the ambush.

Amra was not a "closely watched inmate", prosecutor Laura Beccuau said, using a term for highly dangerous prisoners.

However his transportation still reportedly required a "level three escort" which meant there were five prison officers travelling with him.

His lawyer, Hugues Vigier, said Amra had already made an escape attempt at the weekend by sawing the bars of his cell, but said he was shocked by the "inexcusable" and "insane" violence.

"This does not correspond to the impression that I had of him," the lawyer told BFMTV.

Mr Vigier said that his assistant had met with Amra on Tuesday morning.

"A short meeting, about an hour long was planned for this morning and my assistant saw Mr Amra and he was perfectly normal," he said.

"He knew about [Tuesday's] transfer so it is possible that he'd have told other people."

His accomplices appeared to be fully informed because they were waiting at the motorway tollbooth.

Amra's mother said he had not given any indication he would try to escape.

"He doesn't talk to me. He's my son, he doesn't talk to me about anything at all."

She said she went to visit him in several of the prisons he's been held in, but "he never gave anything away. I don't understand".

She described breaking down in tears after hearing about the ambush.

"I broke down, I cried - I was so unwell - how can lives be taken away in this way?" she told RTL.

She also described her son's life in the prison system, saying he was "lugged around left right and centre, they put him in isolation instead of sentencing him once and for all".

He had been held in separate prisons in Marseille, Paris and Rouen during the legal process against him for theft, which resulted in an 18-month jail sentence.

He had 13 previous convictions for largely minor offences, including driving without a licence, theft and refusing to stop for police, according to BFMTV.

However his implication in the death of a man from Dreux near Rouen who was kidnapped in Marseille in acts linked to drug trafficking suggests involvement with more serious criminals.

The heavily armed attack that freed him came on the same day as the French Senate published a report warning France was being "submerged" by drugs crime.

The report notes an "explosion of both supply and demand" in the illegal drugs trade, warning: "No part of the national territory and no social class is beyond the reach of drugs crime… drugs traffic is infiltrating everywhere, with a concomitant exacerbation of violence".

The trade in drugs has spread across the country, making inroads in rural areas and medium-sized towns, it said.

"The spread of drugs crime is not just the result of foreign mafias. It is also the work of structured and dangerous French organisations who act without any limit be it financial, territorial or in the exercise of violence," the report said.

Yesterday Nicolas Bessone, the prosecutor for the Marseille region, told broadcaster France 2 that drug gangs had become so rich and powerful they were successfully infiltrating the court system in Marseille, corrupting civil servants.

Around 50 people were killed in drug-related shootings in Marseille last year.