People trying to cross the Channel to the UK have reported an increase in French police use of violence on beaches to prevent them from getting into dinghies, according to a French NGO.

Utopia 56, which works on beaches from where migrants attempt Channel crossings, says so far this year 2,720 people have reported being victims of French police violence, compared with 1,954 over the same period last year, when crossings overall were much higher.

The organisation says that due to increased enforcement activity on French beaches, for which the UK provides funding, crossings have become more dangerous and disorganised, putting more lives at risk. So far this year at least 21 people have died trying to cross the Channel to reach the UK.

The NGO’s report alleges that the UK and French governments are “the architects of this chaos”. It calls for an overhaul of the European asylum system and the opening of safe routes, which it says would stop the boats and neutralise the smugglers.

Under a £660m deal agreed earlier this year between the UK and France, the latter has deployed a riot squad to try to stop the boats. Reports of violence include beatings and use of teargas. According to Utopia 56, teargas canisters were deployed during the recent heatwave in sand dunes, posing a fire risk.

The NGO has documented at least 10 families becoming separated on French beaches as a result of enforcement action. In one case documented on 27 July, a woman’s leg was run over by a French gendarmerie buggy racing across a beach to try to stop a group of migrants.

The briefing, titled “Behind the figures: violent practices, the human cost of repression on the French coast”, has been produced in response to a Home Office announcement widely reported on Friday about the success of increased enforcement to stop the boats.

Crossings have decreased by more than 40% so far this year compared with the same period last year and the numbers crossing in July were the lowest recorded for the month since 2020.

The Home Office stated that between 27 April and 2 August, French officers prevented 185 boats and more than 4,300 people from crossing the Channel. It is not known how many of these people subsequently succeeded in making the crossing.

The Utopia 56 report says: “People do not simply vanish after being intercepted, contrary to what one might believe upon reading the British government statement.”

The Home Office said a large amount of equipment had been seized including boats, engines and lifejackets. According to Utopia 56, the seizure of lifejackets does not deter the smugglers but increases the chances that people will drown.

“This is a policy driven by statistics, implemented with a single goal, stopping the boats, without any regard for the suffering it causes,” the report says. “These figures may appear to prove that the crackdown is working, but they fail to account for the consequences: women, men and children abandoned on beaches – and, above all, many falling victim to the excesses of the security operation and, consequently, to police violence.”

A Home Office spokesperson said: “This government is bearing down on dangerous small boat crossings and restoring control at our border. Joint efforts have seen over 48,000 crossing attempts prevented and 1,100 boats and engines seized since the election.

“We are making progress, with the number of small boat crossings down this year and the lowest number recorded for the month of July since 2020. But we must go further, which is why we have signed a payment-by-results deal with the French to put 40% more boots on the ground on French beaches.”

France’s interior ministry was approached for comment.