A 34-year-old man has been arrested on suspicion of the murder of nine-year-old Olivia Pratt-Korbel.
Olivia was shot in the chest in her home in Dovecot, Liverpool, on August 22.
Her mother, Cheryl Korbel, 46, was also injured when a gunman chased his target, convicted burglar Joseph Nee, into their property at about 10pm.
Merseyside Police said on Thursday evening that a man from the area has been taken to a police station where he will be questioned by detectives.
Officers said the investigation into Olivia’s murder is ongoing and continues the appeal for information.
The reward offered in the hunt for the killer had been increased to £200,000.
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