South Yorkshire Police has already referred itself to the Police Complaints Commission over its involvement in the "Battle of Orgreave".
But they say any inquiry would take some time because of how long ago the events took place.
Fighting broke out between miners and police at Orgreave Colliery during the miners' strike in 1984.
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Fine with a cold wind
Slowly becoming milder. Unsettled end to the week.
The National Housing Federation says the average worker in the region would need a 62% pay rise in order to afford a mortgage.