Police have evacuated 32 houses on Wisden Road after discovering items which may be explosive.
The items were discovered in a bin shed this morning after a man was arrested due to an unrelated event and his property was searched.
A police officer at the scene said: "While searching his flat this morning we found some items which may be explosive."
The bomb disposal team has set up a 50m corden on Wisden Road and are advising the public to avoid the area.
READ MORE: Stevenage street cordoned off as police await arrival of bomb squad
The officer added: "There is nothing to indicate the male who was arrested has anything to do with terrorism."
He confirmed counter-terrorism officers had been and left after finding nothing.
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