MADRID (AP) — Some British citizens trying to return to their homes in Spain and other European countries have been barred from boarding flights this weekend. Airlines are refusing documents that before Brexit had been valid proof of their status as residents in Spain. It’s not clear whether Brexit or new travel restrictions against people coming from Britain are to blame. Their ordeal comes amid heightened travel restrictions due to a coronavirus variant that has been blamed for faster contagion in the United Kingdom. It also highlights the bureaucratic complexities resulting from Britain’s departure from the European Union. Around 300,000 British citizens are registered as permanent residents in Spain but before Brexit, many more lived fulltime or part-time in the country.