Two Ukrainian men are being questioned under anti terror laws after explosions near mosques.
West Midlands said they had found debris and signs of an explosion on a roundabout near the central mosque in Wolverhampton.
The find was made following yesterday's arrest of two men in Small Heath, Birmingham, in connection with blasts close to mosques in Walsall and Tipton.
The men, aged 25 and 22, are being questioned on suspicion of being involved in the commission, preparation or instigation of an act of terrorism.
A police spokesman confirmed that last night's discovery was made on the Fiveways traffic island by officers and Army bomb disposal experts as they searched land around the Wolverhampton mosque.
The spokesman said: "The debris, found on Fiveways roundabout, has been declared safe and further detailed forensic inquiries will be conducted at the scene throughout the day.
"Nothing was found at the mosque itself which has now been reopened for worship.
"The searches were initiated following the arrest of two men in Small Heath yesterday who are suspected of
involvement in explosions near mosques in Walsall and Tipton.
"Officers remain at the mosque and patrols in the area have been increased to reassure members of the public concerned by events."