Officers in Wiltshire say they've had reports of it happening between Junctions 19 and 15.
Bristol children get ready for big school
Thousands of children in the final year of primary school in Bristol will be visiting their new secondary school over the next two weeks.
Bristol's Transitions Fortnight runs from 25 June to 6 July and aims to help children have a successful move to their new school.
More than 3,000 children will be starting secondary school in Bristol for the first time in September. Research shows that where children experience a successful transition, they have a wider circle of friends, increased self-confidence once at secondary school and settle more quickly into life at their new school.
More families are choosing Bristol secondary schools with a rise to 87 per cent on offers accepted this year.
One of the main factors supporting children in a successful move is the amount of help they receive from their new secondary school. This includes visits to school, induction and taster days, help with getting to know their way around the school, and information, encouragement, support and assistance with lessons and homework.
Cabinet Member for Children and Young People, Councillor Clare Campion-Smith, said: ''The move from primary to secondary school is a very important time for children and their families. For many children it is an exciting time, but for others there can be feelings of uncertainty and anxiety.
''Secondary schools across Bristol are using the next two weeks as an opportunity to welcome their new students and help them find their way round and meet their peers. The visits are designed to ensure they settle in well when the new school year starts in September. I wish Bristol children every success as they set out on their new school career.''
Head teacher at Henbury Secondary School, Clare Bradford, said: ''Children come to our school from more than 20 different primary schools, so it is very important we support them as they get to know each other and settle into studying at secondary level. Weâ€™ve listened to current students who have explained the things they felt anxious about before making the move and have thought about how we can help children with these issues.''
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