Police have vowed to bring to justice a pair of brothers who were filmed attacking a McDonalds worker.
They said that they have received multiple reports identifying the attackers whose mother has spoken out to criticise their behaviour.
They were allegedly with their father when they locked a member of staff in a cupboard and flicked a workers cap before beating up the manager who asked them to leave.
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As the attack began on Tuesday night, it has been reported that their father walked out of the restaurant in Boston, Lincolnshire, and sat in the car to wait for them.
Chief inspector Deborah Clark said: We are taking this extremely seriously and we are making good progress with our enquiries.
The media exposure has resulted in many reports from the public and we are grateful for their support.
This is totally unacceptable and shocking behaviour that no one should have to be subjected to and we will do all we can to bring the offenders to justice.
The boys, believed to be aged 16 and 19, were apparently drunk when the attack happened.
Their mum wrote: I know what had happened and it is not acceptable, im very sad and ashamed that my boys would do this and it will be being sorted you would appreciate the rest of the family being left out of it and for the hate comments to stop.
I am a caring normal loving mum they are my sons and Im broken enough!
They will be dealt with as will the situation. These sort of things happen every day and all get to easily forgotten but never do you think its going to be something to do with your family!! Im very sorry on behalf of my boys.
Witness Jasmine Brudenall, 28, filmed it all. She said: I sensed it was going to erupt. Sometimes you can tell when someone is so drunk that there is no chance of reasoning with them.
They were so intoxicated, There was no stopping this – they would have hit anyone who got in the way.
The other side of where people were eating were kids and old people. All the other guys were friends with them and carried on laughing.
When outside at the front off the store they, used a metal bar they pulled off door and tried to hit him.
The McDonalds staff member took a lot of punches. After theyd gone, [he] went into the back.
One person who watched the drama unfold, said: The young lads wanted a fight from the beginning – they were being really stupid and were shouting and swearing at the workers.
The two lads who were fighting were drunk. One of the boys was trying to lock one member of staff in the toilets.
The manager told a member of staff to go over and tell them to leave and then it all just went off.
There were 10-year-olds there with their parents – anyone who stepped in was going to get a beating.
She added: The McDonalds employee was able to keep them away from the kids. My heart was beating. There was just a feeling of shock, everyone was gobsmacked – it was not nice. It was a heroic but horrible incident for the staff member.