“Don’t let people take the law into their own hands. Instead, give him a fair sentence,” the 18-year-old’s parents wrote in an open letter published Thursday in the local Sydsvenska Dagbladet newspaper.

The teenager, who attacked Helsingborg goalkeeper Pär Hansson before being wrestled to the ground by police and other players, told police after the match he ran onto the field because he was “pissed off” that visiting Helsinborg had just scored a goal, the Aftonbladet newspaper reported.

In the wake of the incident, which has prompted condemnation from high ranking football officials as well as Prime Minister Fredrik Reinfeldt, the 18-year-old has faced a barrage of threats on the internet.

Fears of reprisals are so high that he now has police posted outside his home, according to the Expressen newspaper.

In their letter, the 18-year-old’s parents call the incident “tragic”, adding that “we don’t defend our son’s actions but we support him as parents because right now we are all he has”.

“Today is a very sad day for us as parents,” they wrote.

“We hope that some other parents can understand our hopeless situation. Parents whose children have also engaged in bad behaviour at football.

“We can only express our sympathies and apologise.”

The 18-year-old admitted to police that he stormed the pitch, but has denied committing any crime. He is suspected of assault and disturbing the peace.

In addition, the teenager may be facing a million-kronor lawsuit from broadcaster Canal Plus, the broadcaster for Tuesday’s match.

“Our point is that we need to get value for our rights and you have to place direct demands on those people who ruin Swedish football,” Canal Plus CEO Johan Kleberg told media trade paper Resumé.

The TV channel has never before taken such measures, often offering instead to supply police with television images to help identify suspected hooligans.

Kleberg added that his company wants to help solve the hooligan problem in Swedish football by means other than purely legal.