TWO brothers - who caused outrage after filming themselves repeatedly stamping on a dog and throwing it downstairs - were forced to call in police after one of them was allegedly assaulted.

Cleveland Police said officers investigated an assault in Redcar earlier this month, but denied that the brothers were under police protection.

The force also warned against vigilantes taking the law into their own hands.

Andrew Frankish, 22, and his brother Daniel, 19, admitted charges of animal cruelty after footage emerged showing Andrew repeatedly attacking a bulldog named Baby, who was later put down. They were given suspended sentences, fined and banned from keeping animals for life, when they appeared at Hartlepool Magistrates Court earlier this year on an RSPCA prosecution.

Almost half a million people have signed an online petition calling on the two men to be given tougher sentences and on Saturday a plane, trailing a banner reading "Jail the Frankish Brothers" was flown over the Riverside Stadium in Middlesbrough.

Rumours on social media suggested that the brothers were under police protection after receiving online threats - but Cleveland Police said yesterday that they were not being protected.

A spokeswoman said: "A 36-year-old man was arrested following a call from occupants of a house in Redcar just after 11.05pm on Sunday, April 3. The man was interviewed and subsequently released with no further police action.

"People may have the best of intentions, but they could put themselves at risk and they can also disrupt police or RSPCA investigations.

"We would advise people not to carry out their own inquiries, but to contact the authorities and raise their concerns so they can be investigated thoroughly and in the safest possible way."

Both brothers, who admitted causing unnecessary suffering to the bulldog, were given a six month curfew by magistrates. They were only caught when a memory card containing the disturbing footage was discovered by a member of the public in a supermarket, who recognised the,.

Redcar's Labour MP Anna Turley was among those to sign the petition for a longer sentence, as Ms Turley said she was "disgusted by their actions".

She has asked Justice Secretary Michael Gove to review the sentence.