Police were unable to locate the bike and its rider.
They were seeking information from anyone who had seen a larger white dirt bike, possibly with a yellow trim, near Gladstone Road and Customhouse Street early this morning.
Police were also seeking anyone who might have information about the incident regarding who was involved.
The incendiary item had been examined, and police inquiries were ongoing.
Anyone with any information could contact police online or call 105, using the reference number P060195550.
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