The case of an asylum seeker accused of punching a mother in front of her children after she caught him stealing from an elderly woman has reignited the debate over migration in Sweden. The suspect was arrested on 22 January after police released a video of the attack which sparked outrage across the country.

Security camera footage from the Gamla Stan metro station in central Stockholm showed a man approaching a pensioner with her bag open to take out a mobile phone. As she is distracted conversing, he walks up behind her.

However, another woman walking in the opposite direction with her two children realises the danger and alerts the victim interrupting the alleged pickpocketing attempt. Angered at the failed theft, the man turns on the woman. He hits her in the stomach and face before rushing back to spit at her, while she tries to shield her two children.

The clip went viral and the attacker was dubbed the most hated man in Sweden. Stefan Tellqvist, a policeman working on the case said it was "the worst thing" he had seen during his career. "I will get him, if it's the last thing I do," he told Aftonbladet newspaper.

A day after the video was released, staff at a centre for failed asylum applicants near the capital alerted authorities to a male resident fitting the description in the footage and the suspect was eventually arrested.

For several days the man's identity remained unclear, as it emerged he had filed for asylum in four European countries (Norway, Greece, Denmark and Sweden) using different aliases. On 25 January his lawyer, Ekrem Gungor, confirmed to IBTimes UK that his client was a 33-year-old Algerian named Sofian.

He was placed in the immigration centre after Sweden refused him asylum and was already known to authorities for violent episodes, including another arrest in January over accusations of threats to a public official, violent resistance and trespassing, according to Aftonbladet.

He remains in custody pending trial but denies the charges of attempted aggravated theft, assault and harassment. At a preliminary hearing he claimed to be a victim of mistaken identity, arguing a Tunisian man with similar features was the real culprit.

After the trial he is to be deported to Denmark under Europe's Dublin regulations where he first requested refugee status. However, if convicted he will be made to serve his sentence in Sweden.

The case comes amid tensions caused by the growing influx of migrants and is likely to further fuel xenophobic sentiment in the country that has witnessed a spike in arson attacks on refugee homes last year.

It follows controversy sparked by revelations in the wake of mass sexual attacks in Germany on New Year's Eve that Swedish police had failed to make public a similar incident involving numerous sexual assaults, often perpetrated by migrant youths, at a music festival in Stockholm last year.

The government recently tightened its traditionally welcoming asylum policy, imposing temporary border controls to cut down the number of arrivals. More than 160,000 people filed for asylum in Sweden in 2015.