Incendiary device 'ignites' at Preston Fishergate Shopping Centre
An "improvised incendiary device" has "ignited" at a shopping centre, causing it to be evacuated, police have said.
The "deliberately planted" device was found in a bin at Preston's Fishergate Shopping Centre at about 09:10 GMT.
Lancashire Police said it had "the potential to cause serious injury if it had exploded".
The force has released CCTV footage of a man they would like to speak to. He is shown walking up an escalator in the nearby St George's Shopping Centre.
An evacuation was ordered "as a precaution" because the incendiary had "gone off, causing very minor damage and no injuries", police said.
An Army bomb disposal unit went to the centre to aid investigations. Officers have recovered the device and are analysing it.
Det Ch Insp Jill Johnston said: "While the motivation for this incident remains unclear at this stage, we believe this device has been left there deliberately and did have the potential to cause serious injury if it had exploded."
Earlier, Ch Supt James Lee said the centre remained closed due to concerns there may be more devices.
He said the incendiary was found by a member of the public in the men's toilets.
"Something happened to it to cause a very small fire, but it was put out immediately," he said.