TRAFFIC CHAOS has been brought to one of Britains busiest motorways after the M25 has had to be closed for the second time in three days - again due to a serious accident involving an overturned lorry. Todays incident, which is resulting in long tailbacks, has resulted in injuries to two people, with one in a critical condition, police said. The stretch of road shut is the M25 between junction 23 at South Mimms in Hertfordshire and junction 25 at the junction with the A10 north of Enfield in north London.