The European Commission is looking into reports the British government is creating a hostile environment for European Union citizens living in the UK.

As reported by Euronews, Brussels is checking whether the UK is violating EU rules by restricting the right of European citizens to move freely around the bloc.

“We’ve been very alarmed by the incredible rise in the numbers of EU nationals being detained and then removed or deported. It’s increased exponentially over the last years,” said Celia Clarke, director of the London-based charity Bail for Immigration Detainees (BID UK).

According to government data, more than 5,300 European citizens were expelled from the UK over the last 12 months. This is a 20% rise from a year ago.

While the UK’s Home Office has explained it is cracking down on criminal offenders, BID UK has warned that many were deported before they were able to initiate a legal challenge.

BID UK released a letter sent by the Home Office to a Romanian citizen informing him he should return to Romania or move to another European country to exercise his fundamental rights and “avoid becoming destitute”.

“It’s acting as if we’re not a member of the EU, by saying ‘you can go exercise your rights in the EU’. But we are still in the EU,” Clarke said.

According to Euronews, the charity shared its concerns with the European Commission.

In a written response, the Directorate General for Justice stressed that as long as the UK remains a member of the EU, all rights and treaty obligations continue to apply to it.

The letter, dated October 20 and seen by Euronews, suggested the Commission is keen to gather more evidence of possible breaches of EU rules by the UK.

“We would be grateful for any information you may want to share with us,” it wrote.

According to Euronews, a Commission representative confirmed the letter was authentic, adding: “We are looking into this issue”.