Police along with East Sussex Fire and Rescue were called to Sussex Skips in Newhaven in the very early hours of this morning (24 July) following an alarm being activated.
On arrival at North Quay Road at 12:40am emergency services discovered a large pile of burning rubbish that was spreading to the main building. Firefighters worked for several hours to extinguish the fire and make safe the area.
Sergeant Dave Tye from East Sussex CID said: "The cause of the fire is yet unknown and we will continue to work with our colleagues at East Sussex Fire and Rescue who are continuing with their forensic examinations of the scene today (24 July).
"If you heard or saw any suspicious activity yesterday evening please call 101 quoting serial 50 of 24/7 or the independent charity Crimestoppers anonymously on 0800 555 111."