Police are investigating an incident which involved a rock being dropped from a bridge onto the M6 near to Houghton Hall garden centre, on the 8th February at about 2.50pm.
A Cumbria Police spokesman said: “The rock fell onto a passing white Mini Cooper, damaging the windscreen.”
Anyone who witnessed this incident or anyone with information is asked to call PC 2838 on 101, or call Crimestoppers anonymously on 0800 555 111, quoting log 126 of the 8th February.