Last night there were demands for more information-sharing across international borders and stronger immigration checks after it emerged there were concerns about the couple in their home country in Europe.

It is understood they fled as similar allegations were being investigated and UK immigration officials were unaware of their history when they arrived in 2003 and moved to Bradford.

It was while living there that the Nigerian father sliced the boys' mouths with a scalpel and left safety pins in their mouths for days – telling them he inflicted the injuries because God had his tongue cut off in the Bible.

Social services chiefs only found out after bruising was seen on one of the boys in 2005.

Last night Shipley MP Philip Davies said: "This is the danger of having free movement of people across the whole of the EU. We have no idea of the nature of people who are coming in and out of the country."

Victoria Climbié Foundation director Mor Dioum said: "We need to develop a mechanism in which countries share informat-ion, especially when parents with children have left that country."

A jury at Bradford Crown Court yesterday found the father, aged 47, guilty of three counts of unlawful wounding and eight of cruelty. The mother was convicted of two counts of cruelty by wilfully failing to protect her sons.

Judge Christopher Prince, remanding the father in custody, said: "You breached the position of trust that parents have to their children and you engaged in a long campaign of pure cruelty as to what has been described by your own counsel as torture to your own children. They must have lived in fear of coming under your gaze and your hand with the instruments that you used to cause such pain to them."

The jury returned guilty verdicts on 13 of 14 counts against the couple but failed to reach a verdict on another charge against the mother.

The boys, aged nine to 10 and seven to eight at the time of the abuse, were beaten and tied up by their father, the court had heard.

He cut their mouths with a scalpel, pressed the older boy's tongue with pincers, beat him with a stick and locked him in a dark room with his legs tied with wires and his eyes and mouth tied with a towel.

The boys' mother did nothing to stop the torture with safety pins or to remove the children from their torment.

Yesterday Det Chief Insp Stan Bates, head of West Yorkshire Police's child and public protection unit, said: "It is believed the motive for this abuse was an extreme religious belief.

"The police are increasingly working with faith groups and the community to raise awareness around child abuse. We are not in the business of challenging or policing religious beliefs. Our priority is to protect children and prevent them being victims of cruelty."

Richard Bates, from Bradford Council, said: "The children are safe in care and are legally protected. We will be working to ensure that they can now have a happy and stable future."

The Border and Immigration Agency said the Government "fully supports, and has already been pushing for, greater data sharing with other European agencies, and would always welcome any moves to extend this joint working relationship".

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