Two migrants have been discovered hiding inside mattresses strapped to the top of a van attempting to cross from Africa to Spain, prompting renewed concerns about asylum rules in Europe.

The men, reportedly of sub-Saharan origin, were arrested by border guards after they were discovered at a check-point between Melilla, a Spanish enclave on the north African coast, and Morocco, according to Spanish news site El Periodico.

Footage shared on Twitter by Spanish senator Jon Inarritu showed the men emerge from the mattresses after men in Guardia Civil uniforms used a knife to cut through the fabric. It is thought to be the first documented attempt to smuggle people inside a mattress, according to local media.

“As long as there are no safe routes to request asylum, situations like this will continue to occur in the southern border of Europe,” Mr Inarritu wrote alongside the video.

The driver of the vehicle allegedly fled into Morocco before authorities could make an arrest. The two men were said to be in good health and did not require medical assistance.

It comes after tech companies were accused of failing to crack down on people-smugglers using their platforms to lure migrants “to their deaths” with the promise of safe passage to Europe.

The UN said companies such as Facebook and WhatsApp were “enabling criminal activity” by traffickers who entrap victims who are unaware of the dangers they face.

Meanwhile there has been a surge in migrants attempting to reach the UK by crossing the Channel in small boats, with more than 100 people intercepted by both British and French authorities while attempting to reach the UK from France since Christmas Day.

But lawyers and campaigners have cautioned that the recent rise has been “blown out of proportion” as the numbers arriving constitute a “tiny proportion” of people coming to Britain to seek asylum.