Abdelhakim Dekhar, 48, remains in custody in Paris hospital after police detained him on Wednesday night.
Here is what we know about him:
- Of Algerian origin
- Enlisted in the Algerian army at the age of 17, Le Figaro reports
- Affiliated with anarchist far-left in the 90s, known as “Toumi’ among his peers
- Sentenced in 1998 for his links to a murder spree in France
- Lived abroad, including in London, after his release in 1999
- Detained on Wednesday, heavily medicated
- Believed to have attempted to take his own life
- Left notes criticising capitalism and the violence in Libya and Syria
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A small number of people were treated at Southgate Tube station, British Transport Police said.