Detectives are investigating after several boats and a boathouse in Aberdeen were set alight at the weekend.
Emergency services were contacted just before 3am on Sunday morning after the fires were reported at Cove Harbour.
Officers are treating the incident as suspicious following inquiries with the Fire and Rescue Service.
Detective Inspector Norman Stevenson said: “We continue to appeal to anyone with information about this incident to get in touch as soon as possible as our inquiries continue.
“This malicious act has deeply affected the fishermen whose livelihoods have also no doubt been affected, and I can’t begin to stress just how disappointing this is.
“We also continue to carry out inquiries into fire-raising and vandalism at the site of the Aberdeen Harbour expansion.
“I appreciate the similarities of both incidents and the close proximity; however, we need to keep an open mind as to whether they are linked.
“In the meantime, additional patrols are being dedicated to both areas to help prevent any similar incidents from occurring.”