George Paul witnessed the arrest of one of the suspects in Westborne Grove and told ITV News he saw "three policemen holding down one individual - I don't know what ethnic origin he was but he was shouting.
"It was all over in ten minutes."
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Fine start to the week for most but turning wet and windy from Wednesday.
Thousands of people have lined the banks of the Mersey to see Cunard's three flagship ocean liners sail down the river.
Claims that surgeons used an old saw found in a cupboard to amputate a patient's leg are being investigated.