A British man accused of plotting a terror attack may have targeted former prime minister Tony Blair and his wife Cherie, jurors in the partly-secret terror trial were told.

Erol Incedal, 26, from London, may also have been looking at a "Mumbai-style" atrocity with Kalashnikov rifles, according to coded messages on his computer, the Old Bailey heard. The Blair address was in his car.

But the alleged plot was scuppered after police stopped Incedal's car for a motoring offence and planted a bugging device which picked up snippets of chatter about "bin Laden, fatwa, Syria and jihad".

Incedal denies charges of preparing acts of terrorism and possessing a document entitled Bomb Making on a memory card.

His co-defendant, Mounir Rarmoul-Bouhadjar, 26, from London, had pleaded guilty to possessing a terrorist document.

Prosecutor Richard Whittam QC said: "You will hear that he (Incedal) was actively engaged with another or others who were abroad. The prosecution case is that such engagement was for an act, or acts of terrorism either against a limited number of individuals of significance or a more wide-ranging and indiscriminate attack such as the one in Mumbai in 2008." The case continues.