Hertfordshire Police are concerned for the safety of drivers after two incidents when it's believed snow or ice were thrown off the Norton Road bridge onto the A1M near Baldock.
The first incident happened at around 9pm on Sunday. A driver travelling northbound in a white Mercedes van, reported that snow or ice hit his windscreen, causing it to crack.
The second incident happened 40 minutes later. This time the driver, who was travelling in a in a blue Isuzu car, reported seeing three or four people drop a large snowball, causing three cracks on the passenger side of his windscreen.
North Herts Safer Neighbourhoods Inspector Danny Lawrence said:
“The danger of targeting vehicles in this manner is totally obvious. The offenders put these drivers at serious risk and could have caused someone to lose their life or even caused multiple fatalities."
“We will be stepping up patrols in the area and will be working hard to trace the suspects whose behaviour could be described at best as utterly reckless and without any regard for the safety of innocent members of the public.”
The RSPB is urging people to help birds this winter by putting out food and fresh water.
Feeding wild birds throughout winter is vital, but one Norfolk wildlife reserve owner has gone further by hand-feeding a tiny robin.
The MP for Colchester Sir Bob Russell has questioned widespread school closures because of the snow.