Abuja, Nigeria CNN  — 

A Nigerian senator, his wife and a doctor were on Friday jailed over an organ harvesting plot involving a young man who was trafficked to the UK for his kidney, Britain’s Crown Prosecution Service (CPS) said in a statement.

Senator Ike Ekweremadu, his wife Beatrice and Dr. Obinna Obeta were sentenced at the UK’s Central Criminal Court, known as the Old Bailey, to nine years and eight months, four years and six months, and 10 years in prison respectively in the first conviction of its kind under Britain’s modern slavery laws.

The three were found guilty in March of trafficking a 21-year-old street trader to the UK to provide a kidney for the Ekweremadus’ daughter Sonia, who according to the CPS statement suffers from deteriorating kidneys and needs regular dialysis.

Prosecutors said the victim was brought to the UK after being offered a reward of up to £7,000 ($8,810) and the promise of work in the country, but was unaware that he was expected to provide a kidney in return.

A medical consultant called off the planned transplant after becoming suspicious of the circumstances surrounding it and the victim fled, sleeping rough for days before reporting the plan to UK police last May, the CPS said.

“This was an horrific plot to exploit a vulnerable victim by trafficking him to the UK for the purpose of transplanting his kidney,” Joanne Jakymec, Chief Crown Prosecutor, was quoted as saying.

“The convicted defendants showed utter disregard for the victim’s welfare, health and well-being and used their considerable influence to a high degree of control throughout, with the victim having limited understanding of what was really going on here,” she continued.

Detective Inspector Esther Richardson, from the Met’s Modern Slavery and Exploitation Command said: “This is a landmark conviction and we commend the victim for his bravery in speaking against these offenders.”

Ekweremadu was a former deputy senate president in Nigeria for 12 years and his case elicited sympathy in Nigeria where some saw him and his wife as victims of circumstance who were desperate to help their sick daughter.

Some of the country’s political class wrote to the UK court appealing for leniency ahead of his sentencing, including Nigeria’s former President Olusegun Obasanjo.

President of the Nigerian Senate, Ahmad Lawan, said Wednesday he wrote to the British judiciary on behalf of Ekweremadu asking them to “temper justice with mercy.”

While Femi Gbajabiamila, the Speaker of Nigeria’s House of Representatives, described Ekweremadu as “a brilliant lawyer, a distinguished public servant and a dedicated family man.”

The speaker of parliament of the West African regional bloc ECOWAS, Sidie Mohamed Tunis said he also written to the chief clerk of the Old Bailey Court seeking leniency for the Ekweremadus.

Ekweremadu served as speaker of the ECOWAS parliament between 2011 and 2015.

But the calls for clemency failed to hold sway over the UK court and some in Nigeria questioned why high profile politicians were using their influence to advocate for a convicted criminal.

IPC Justice, a non-governmental organization dedicated to fighting corruption in politics wrote on Twitter: “… Nigeria has a reputation for not enforcing laws against political elites, which could lead to the perception of condoning criminal activity if the Speaker advocates for clemency for someone convicted of a serious crime.”