The Police and Crime Commissioner for Thames Valley has said he will call for a review of the force's search for Leah Croucher if he feels mistakes have been made.
Matthew Barber's comments came after police revealed at a press conference they had made 18 attempts to arrest Leah Croucher murder suspect Neil Maxwell while he was on the run following an alleged sexual assault four months before Leah disappeared.
Maxwell later took his own life in April 2019 before the police found him.
Mr Barber said he had asked the chief constable to give him a review of the case to work out if any further inquiry was required.
He said: "If mistakes have been made I will ensure a thorough review of the missing persons investigation, but I must stress that this will be evidence-led and so far I have seen nothing to suggest any reasonable lines of enquiry were missed."
Mr Barber described recent events in the Leah Croucher inquiry as a "bitter blow" for Milton Keynes.
He said Leah's disappearance had 'hung over the community' since 2019 and hundreds of officers had conducted thousands of house-to-house inquiries.
“Given the time that has passed questions have inevitably been raised about the earlier investigation and there is an understandable desire for more information. None of the information I have received so far leads me to conclude that there were shortcomings in the earlier missing persons investigation."
He said the priority now was the murder investigation as Leah's family come to terms with what he described as "this heartbreaking news."
Police have named Neil Maxwell as the prime suspect in Leah's murder after her belongings were found alongside human remains at a home in Milton Keynes where he had been a handyman.
Leah disappeared while walking to work on February 15 2019.
Detective Chief Superintendent Ian Hunter told a press conference in Milton Keynes that prior to the alleged murder, Maxwell had been wanted in connection with a sexual assault in Newport Pagnell in November 2018.
He said police had pursued “every reasonable line of inquiry” in Leah’s case over the past three-and-a-half years, including reviewing 1,200 hours of CCTV, conducting more than 4,000 house-to-house inquiries, and searching lakes, open land and woodland.
During these inquiries police visited 2 Loxbeare Drive on “at least” two occasions, but there was no response at the house.
When no one answered at the property, police left a leaflet requesting a call back, and also visited the property to scope what CCTV was available in the area.
Mr Hunter said: “But sadly, the call from the member of the public that we received on Monday was the first occasion that information was made available to enable the investigation team to provide any link between that address in Loxbeare Drive and Leah.”