A man from West Yorkshire is one of seven arrested on suspicion of terror offences after firearms and other weapons were discovered in car.
West Midlands Police have confirmed that one man from West Yorkshire and six others from the West Midlands are being questioned.
It is after a car was routinely stopped on the M1 motorway, between junctions 33 and 34 near Sheffield, on Saturday June 30. It was impounded on suspicion of not having insurance.
Three men aged 23, 26 and 27 were arrested on Tuesday morning. Three more aged 22, 24 and 27 were arrested on Wednesday evening. A 43-year-old man from Kirklees was detained on Thursday. All seven men are being held in the West Midlands.
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