Two more people have been charged with conspiracy to murder and intending to smuggle explosives onto aircraft in the alleged bomb plot thwarted by police.
Other men are facing charges over the alleged bomb plot
Mohammed Shamin Uddin and Mohammed Yasar Gulzar were charged late on Tuesday, hours after Nabeel Hussain was charged with the same offences.
All three are due to appear at City of Westminster Magistrates' Court on Wednesday, Scotland Yard said.
Five people remain in custody while eight men have already been remanded.
Four other people are facing lesser charges.
Police are also questioning five other people held after a series of raids in London, Birmingham and High Wycombe.
Officers have until Wednesday to question the five, after which time they may charge or release them or apply for a further extension.
Police allege that Mr Uddin and Mr Gulzar, between 1 January and 10 August 2006, conspired with other persons to murder other persons.
They are also accused of intending "to smuggle the component parts of improvised explosive devices onto aircraft and assemble and detonate them on board" contrary to section 5 (1) of the Terrorism Act 2006
Mr Hussain, 22, from north east London, was charged with conspiracy to murder and with a new offence of preparing an act of terrorism under section 5(1) of the Terrorism Act 2006.
Earlier on Tuesday he had failed to challenge his continued detention, when two High Court judges said a previous ruling extending his detention was not open to judicial review.
Mr Hussain's brothers, Mehran and Umair, are among the four people facing less serious charges.
They have been accused of failing to disclose information about Nabeel Hussain's alleged activities.
A 17-year-old youth made a second appearance at City of Westminster Magistrates' Court on Tuesday over the alleged bomb plot.
And Cossar Ali - a 23-year-old mother of an eight-month-old baby from Walthamstow, east London - also appeared in court for a second time.