David Carrick has been accused of a total of 14 alleged offences against four women.
Detective constable Francois Olwage denies a series of child sex offences.
The probe would also extend to Boris Johnson's immediate predecessors as prime minister, as well as Conservative party officials.
Police Scotland officers assisting Metropolitan Police in the search for the teenagers.
Serving Metropolitan Police officer appears in court charged with kidnapping and killing the 33-year-old.
Rutherglen and Hamilton West MP Margaret Ferrier travelled by rail despite knowing she had coronavirus.