Armed police were deployed in Ribbleton as a man threatened to harm himself.
Pictures sent to Blog Preston show eight police vehicles in attendance at a house.
An eyewitness claimed police had guns drawn while at the property.
The incident was the junction of Croasdale Avenue with Heathfield Drive at Brookfield.
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Police have been in attendance since shortly before 9.30am on Tuesday (9 October).
A man was seen being led away from the property around 1pm.
A police spokesman said: “We were called around 9.40am today to reports of a concern for safety in Ribbleton.
“A man had threatened to harm himself at a property in Heathfield Drive.
“Officers attended and following negotiation the man left the property.
“He has been taken to hospital for treatment.”