Migrants seeking legal status in Spain broke into brawls while queuing, frustrated by delays following a mass legalisation drive by the socialist government.

As of early last week, Spain's migrant regularisation process was underway, with individuals waiting hours at more than 400 locations across the country for appointments after submitting online applications.

Migrants have been pictured in endless queues outside registry offices in regions such as Catalonia, Andalucia and Madrid. 

In a desperate rush to finalise their paperwork, some migrants have been waiting in line for hours or staying overnight to get their documents officially stamped.

Tensions have been rising as the crowds have overwhelmed registry offices and those seeking to confirm their legal status have begun to grow restless.

Meanwhile, new reports indicate that many individuals granted legal status may have criminal records, as flawed training led officials to neglect requesting the necessary document during the process. 

Earlier this week, violence erupted outside a registry centre in Murcia, a city on Spain's southeastern coast.

Video footage captured a chaotic brawl among a group of male migrants while hundreds looked on, with long queues lining the nearby buildings. 

Police union representative Adrian Rodriguez said the chaos occurred due to growing pressure in the queue, with large numbers of people waiting to be seen.

Reinforcement had to be sent as officers from the Police Response Unit were unable to control the fighting crowd. No arrests were made, according to local reports. 

Rodriguez said the system is under strain as demand has skyrocketed, with Murcia City Council confirming it processed 1,463 vulnerability reports in just one week, a 70 per cent increase compared to the same period last year. 

He said: ‘We were expecting this, and now we’re starting to see the first problems.’ 

It comes as new information has emerged that hundreds of migrants may have obtained legal status without providing a criminal record certificate.

For the first five days of the mass regularization process, postal clerks were forced to use a training manual containing errors.

The manual, seen by Spanish news outlet ABC, does not state that submitting a criminal record certificate is mandatory for undocumented immigrants who have worked during their stay in Spain or who currently have a valid contract.

Consequently, some migrants may have submitted incomplete documentation. 

Meanwhile on Tuesday, a group of desperate migrants scaled the walls of the Gambian embassy in Madrid after being unable to secure the vulnerability certificates needed for their applications.

Many had spent the entire night queuing outside the building just to obtain the required documentation.

However, they were informed early that morning that all appointments were already booked.

The situation then spiraled out of control as migrants began jumping over the embassy fence in a desperate bid to obtain their certificate.

Panic ensued and the police were forced to intervene. No arrests were made, according to local media reports.

Officials in Spain have warned of a collapse in social services as thousands of migrants attempt to gain legal status.

Municipal unions in Seville last week warned that 'extraordinary pressure' and overcrowding are lowering service quality and creating high tension among staff and the public in the Andalusian city.

Unions are pleading for more staff, an improvement in security, and compensation for workers forced to face the chaos.

In Spain's capital, Madrid, services are also under mounting pressure.

'We've gone from 1,500 daily requests at social services centres to 5,500. I think a hasty decision was made, perhaps even intended to create a collapse,' said Jose Fernandez, the municipal delegate for Social Policies.

Fernandez explained to news outlet 20minutos that the process was launched 'without consulting the relevant authorities.'

The initiative by the Spanish government has faced intense backlash from Spanish right-wing parties.

The country's opposition Popular Party has deemed the drive reckless, despite former conservative governments pushing through similar measures.

 Isabel Diaz Ayuso, president of the community of Madrid and a prominent figure in the party, has threatened to appeal the drive in court.

And Santiago Abascal, the leader of the populist hard-Right party Vox, accused the Socialist-led coalition of accelerating what he called an 'invasion'. 

Hitting back at critics, Sanchez sent a message last weekend to what he called the 'extreme right.'

‘Spain is the daughter of migration and will not become the mother of xenophobia,’ he said at a progressive summit in Barcelona.

The government's amnesty is a central plank of Sanchez's progressive agenda to harness the economic benefits of migration for its ageing population, even as other European governments move to tighten their borders.

Sanchez argues immigrants are key to Spain's economy, which expanded 2.8 per cent last year - more than twice the average expected in the entire eurozone.

'Spain is ageing... Without more people working and contributing to the economy, our prosperity slows, and our public services suffer,' he wrote in an open letter addressed to citizens.