Two women in the 20s were taken into a car and raped four days later. The abductions took place in Chingford, in Waltham Forest, and Edgware, Barnet.
Detectives from the Metropolitan Police are now investigating Mr McCann in connection with a number of other attacks on Sunday.
These include the false imprisonment of a woman in Haslingden, Lancashire, in which a teenage girl and a boy, 11, were raped and the abduction and rape of a 71-year-old in Bury, Manchester.
The suspect is also being investigated over the abduction of two 13-year-old boys and the abduction and sexual assault of a 13-year-old girl in Heywood, Manchester, at about 3.30pm on Sunday.
