Detectives investigating three reports of pellets being fired at moving vehicles on the M20 have arrested five people.
The attacks happened one evening last month on the London-bound section of the M20 at the junction with the M26.
At least one motorist was hurt.
A 17 year old woman, an 18 year-old man and a 19 year-old man, all from West Malling, had already been arrested on suspicion of criminal damage with intent to endanger life.
This morning a 15 year-old boy and a 20 year-old man, both from West Malling, were arrested and are currently in custody.