A man seen loitering around a landscaping business in Massachusetts is the main suspect in the theft of 1,000lb of fertiliser.
US police say the bags of ammonium nitrate taken from the business in Whitman could be used to make bombs and rocket fuel.
Whitman Farm owner James McKay says he saw a man with olive-coloured skin hanging around on October 19.
He says the suspect was wearing a button-down shirt, neatly creased trousers and shiny black shoes and fled in a white Ford van.
Whitman Town Administrator Brian O'Connell told a local newspaper: "It hardly sounds like a farmer who was down on his luck. The theft of a product of that nature and that amount certainly is cause for concern."