The attacks on migrants leaving The Jungle or near the border have left two people in intensive care with life-threatening injuries.
They mark a sudden increase in the level and frequency of violence around the camp and more than 50 incidents have been documented in the last three weeks.
A team from the camp’s legal centre has filed eight complaints of police brutality and five against civilian militias to the French judiciary, according to Care4Calais, a British charity that helped compile some of the incident reports.
Victims include a 10-year-old boy who was subjected to police violence and a 13-year-old who suffered a broken foot and broken nose, the charity’s founder Clare Moseley said.
Ms Moseley said she had interviewed a 16-year-old boy who was first beaten with sticks by police, who handcuffed his arms behind his back, and then by a civilian militia.
She said: “These incredibly worrying claims compound the urgency of unprovoked brutality.
“These refugees have come here because they have no choice. They have fled from horrific circumstances. For these things to happen to them shows a total disregard for humanity.”
Marianne Humbersot from the legal centre, who is demanding an investigation by French authorities, said civilian militias were armed and organised.
She said: “We are seeing increasing breaches of human rights here in Calais - everything you can imagine. And the refugees, who have already endured so much to escape conflict, are finding themselves at the centre of hostility and violence here in France.”
The charity Medicin Sans Frontieres (MSF) has treated some of the victims and its staff have seen injuries, some of which have been life threatening, including fractures, stabbings, broken bones, head trauma and severe bruising.
Dr Marlene Malfait, MSF medical co-ordinator at the camp clinic, said: “Some of the injuries are severe, resulting in fractures, now averaging 12 cases a week.”