The woman involved in the incident had a minor injury, thought likely to be from the bladed object, and was treated. The child was not hurt, and both are now being supported.
“This was a volatile and unpredictable incident where there was an immediate threat to life,” said Detective Senior Sergeant Tim Leitch.
“We would like to thank the members of the public who called 111 without hesitation.”
Police know others may have seen or helped during the incident but have not yet come forward.
They are asking anyone with information to contact them online or by calling 105, using file number 250109/0508.
Because the man was injured, the case has been referred to the Independent Police Conduct Authority.
Charges are being considered as the investigation continues.
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