Police say the car - a red hatchback - was last seen driving north on Boston Manor Road toward the A4:
- Witnesses report seeing two white inside the car
- The car is described as being "dirty"
- Police say the vehicle would have damage to its front
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Mr Dobran had been induced into a coma for several weeks following the August attack, before being moved to a nursing home.
The Cranberries singer Dolores O'Riordan has died in London at the age of 46, her publicist has confirmed.
The body of the girl, who has only been named as Baby M by officers, was discovered at the edge of Manor Park in Aldershot.