The women are believed to be Amanda Hyett, 25, of Moorside Road, Dewsbury Moor, the sister of Shannon's stepfather Craig Meehan, and his mother, Alice Meehan, 49.

The 25-year-old woman had been arrested on suspicion of assisting an offender while the 49-year-old woman was being questioned on suspicion of attempting to pervert the course of justice.

Shannon went missing in Dewsbury on February 19 and was discovered in the base of a bed at an address in Batley Carr, just one mile from her home, after a dramatic 24-day police search.

She had vanished after returning from a school swimming trip.

Michael Donovan, of Lidgate Gardens, Batley Carr, was arrested on March 14 after the youngster was found at his flat. Donovan, 39, has been charged with Shannon's kidnap and imprisonment. His trial has been provisionally set for November 11 at Leeds Crown Court.

Donovan, formerly known as Paul Drake, is the uncle of Shannon's stepfather, Craig Meehan.

Meehan, 22, has appeared at Dewsbury Magistrates' Court charged with 11 counts of possessing indecent images of children. He was remanded in custody to appear again before the same court on April 11.

Mrs Hyett lives with her husband Neil Hyett, 35, next door to Karen Matthews and her family on Moorside Road in Dewsbury. During the hunt for Shannon police searched their home and garden.