An arsonist is believed to have started nine fires in bins in Brighton and Hove in little over three hours on one night.
The nine fires, mostly in the Seven Dials area, follow similar fires in Hove over the past few weeks.
East Sussex Fire and Rescue Service sent a crew to tackle each separate blaze.
Sussex Police said: “Police are linking a series of bin fires in Brighton and Hove.
“On Wednesday (25 October) night into Thursday morning (26 October), firefighters dealt with fires in bins in Vernon Terrace, Windlesham Gardens, Davigdor Road, Sillwood Street, Leopold Road, Albert Road, Nizells Avenue, Montpelier Crescent and Western Road, Hove, between 11.30pm and 2.45am.
“This follows similar incidents in Hove over the last couple of weeks.
“Anyone who has witnessed suspicious activity or who has information about who is responsible is asked to report online to sussex.police.uk/appealresponse or call 101 quoting serial 1581 of 25/10.
“Alternatively, you can call the independent charity Crimestoppers anonymously on 0800 555111.”
As well as concerns that a fire might spread, each incident takes fire crews away from where they may be needed if a more serious fire or accident needs their attendance.