The death of a three-year-old boy at a flagship hospital is being investigated by police.

He died at the Queen Elizabeth University Hospital (QEUH) in Glasgow on August 9 2017.

The Mail on Sunday reported his death came in the same month as 10-year-old Milly Main, who was in remission from leukaemia before contracting an infection at QEUH.

Her mother Kimberly Darroch has said she is "100%" certain contaminated water caused the infection.

The death was reported to the Crown Office by Police Scotland in August 2017 and it has recently received expert reports from NHS Greater Glasgow and Clyde (NHSGGC) that are currently under consideration.

A Crown Office spokesman said: "The procurator fiscal has received a report in connection with the death of a three-year-old boy at the Queen Elizabeth University Hospital on August 9 2017.

"The investigation into the death, under the direction of Scottish Fatalities Investigation Unit (SFIU), is ongoing and the family will continue to be kept updated in relation to any significant developments."

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The procurator fiscal has a duty to investigate all sudden and unexplained deaths, as well as deaths which have occurred in circumstances that give rise to serious public concern.

A Police Scotland spokesman said: "A report was submitted to the procurator fiscal in connection with the death of a three-year-old boy at Queen Elizabeth University Hospital in 2017."

An NHSGGC spokeswoman said: "We have already provided information to this family but are sorry that they have further questions.

"We fully investigated this child's death at the time and also asked for two independent experts to investigate the case, the outcome of which has been communicated to the family.

"We are absolutely committed to providing patients and families with information and ensuring they get answers to the questions they have.

"In this case the full findings were shared with the family."

On the issue of Milly Main's death, the health board said it was not obliged to test for bloodstream infection stenotrophomonas - listed as a possible cause on the child's death certificate - at the time of her death and therefore could not determine whether the infection was linked to the hospital's water supply.

Labour MSP Anas Sarwar has called for the health board to be put into special measures and said it was not fit for purpose.

Two wards at the Royal Hospital for Children in Glasgow were closed last September and patients moved to the adjoining QEUH as Health Protection Scotland (HPS) investigated water contamination incidents.

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An HPS investigation found 23 cases of bloodstream infections with organisms potentially linked to water contamination were identified between January 29 and September 26, 2018.

But a whistle-blower told Mr Sarwar a clinician-led investigation found up to 26 cases of water supply infections in children in the cancer wards in 2017 and that one child with cancer died after contracting an infection.

NHSGGC has said it is not possible to link cases of stenotrophomonas infection in 2017 to the water supply as tests were not carried out on the supply at the time.

It said it was "extremely disappointing" that a whistle-blower has made this claim, causing "additional distress to families and to other families of cancer patients".

The health board said it has offered to meet Milly's family and said water in the hospital is safe and has been independently assessed as such.