A teenage son of a British diplomat has been arrested during a probe into a chemical weapons terror threat, according to reports.
The Sun reported that one of the twin sons of Foreign Office First Secretary Nicholas Sutcliffe has been taken for questioning by specialist officers. Sutcliffe has served in the British embassies in the Brazil and Cuba.
The 19-year-old has since been released on bail. He is one of the diplomat's four sons, with wife Carole.
Tents in the garden of the Streatham home
The house in Streatham is being combed by weapons experts, after an early morning raid.
Tents have been put up in the garden, with chemical and biological experts dressed in white hazard suits.
Another 36-year-old woman was arrested on Monday in connection with the investigation. She remains in police custody.
A Scotland Yard spokesman said searches were being carried out as a precautionary measure and that neighbours were not at risk.