Update - 12.35pm: A4 reopens after police investigation

Update - 12.35pm: The A4 has now been reopened after a police investigation but drivers are being advised to continue avoiding the area for the next 30 minutes while traffic flows return to normal.

THE A4 is currently shut as police carry out an investigation into an unknown incident. 

The closure, between the A340 Theale roundabout and the A340 Aldermaston roundabout, is likely to be in place for sometime.

Drivers are being advised to find an alternative route - the M4 for motorway vehicles.

Further information will be published when available.