A suspected al-Qaeda operative has been convicted of a plot to spread the deadly poison ricin on the streets of Britain. Kamel Bourgass had earlier been convicted of murdering a police officer who raided a flat in Manchester where he was staying in January 2003. This is a reminder of the events.
Police found 22 castor beans at the flat in Wood Green
11 Dec: Kamel Bourgass loses his final appeal against refusal to grant him asylum in UK.
22 Jun: Police search a storage depot in Wembley, north London, and find a false passport for Bourgass.
Sep: Police raid a flat in Ilford, east London, and arrest Mouloud Sihali. Police arrest David Khalef at a house in Thetford, Norfolk.
Mohamed Meguerba is also arrested, although he is later freed on bail with his significance unrecognised.
5 Jan: UK police find 22 castor oil beans - the raw material for the poison ricin - in a flat at 352B High Road, Wood Green, in north London. They also find equipment needed to produce ricin and recipes for ricin, cyanide and several other poisons. Seven people are arrested, including Sidali Feddag. Bourgass flees to Manchester, via Bournemouth and Weymouth.
7 Jan: Mustapha Taleb is arrested as he visits a bank in Wood Green.
11/12 Jan: Six people are arrested in Bournemouth, in connection with a ricin plot.
13 Jan: Four people, including Feddag and Taleb, are charged with "possession of articles of value to a terrorist" in relation to a ricin plot.
14 Jan: Detective Constable Stephen Oake is stabbed to death by Bourgass during a raid on a flat in the Crumpsall district of Manchester. Bourgass and two other men are arrested.
20 Jan: Seven people are arrested at the Finsbury Park mosque, north London. Police find weapons, forged passports and ID cards. They also take away a photocopier for examination.
22 Jan: Eight people are charged with offences related to developing or producing a chemical weapon contrary to section one of the Criminal Law Act 1977. Police also arrest Mouloud Bouhrama at an address in London.
Police carried out raids in Manchester in April 2004
30 Sep: Kamel Merzoug is arrested after his fingerprints are found on the poison recipes.
30 Jun: Bourgass is convicted at the Old Bailey of the murder of DC Oake. He is sentenced to life imprisonment. The verdict remains secret due to reporting restrictions designed to give him a fair trial on the ricin charges.
Sep: The trial begins at the Old Bailey of Bourgass, Mouloud Sihali, David Aissa Khalef, Sidali Feddag and Mustapha Taleb. Reporting restrictions remain in place to ensure a fair trial for four defendants in a separate trial.
8 Apr: Sihali, Khalef, Feddag and Taleb are acquitted of conspiracy to commit murder and conspiracy to cause a public nuisance in relation to the ricin plot. Bourgass is convicted of conspiracy to cause a public nuisance. Sihali and Khalef are convicted of possessing false passports.
12 Apr: The jury is discharged after failing to reach a verdict on the second count against Bourgass - conspiracy to commit murder.
13 Apr: The Crown Prosecution Service decides not to go ahead with a second ricin conspiracy trial, involving defendants Samir Asli, Khalid Alwerfeli, Mouloud Bouhrama and Kamel Merzoug. All are cleared. The CPS also abandons plans for a retrial of Bourgass on the conspiracy to commit murder charge.