GENEVA (Reuters) - Egypt must stop executions until it has reviewed all death sentences and retry any convictions that are found to rest on unfair trials, five independent U.N. human rights experts said on Friday.

Egypt’s mission to the United Nations in Geneva did not immediately comment on the appeal, but Egyptian prosecution and judicial sources rejected the criticism.

“We have raised multiple specific cases with the Egyptian authorities and continue to receive more. In the light of these persistent serious allegations, we urge the Government to halt all pending executions,” the experts said in a statement.

“The authorities should ensure that all death sentences are reviewed and, where convictions were based on unfair trials, ensure that individuals have retrials during which Egypt’s human rights obligations are fully respected.”

An Islamic State insurgency in North Sinai has expanded to include civilian targets in the past year. Egypt this month renewed its state of emergency for three more months, broadening the power of authorities to crack down on what it calls enemies of the state.

The five experts who issued the statement - special rapporteurs reporting to the U.N. Human Rights Council - said the death penalty should be used only for the most serious crimes and after a process with all legal safeguards.

The experts were José Antonio Guevara Bermúdez, Agnes Callamard, Bernard Duhaime, Nils Melzer, and Fionnuala D. Ní Aoláin, who report to the Council on arbitrary detention, extrajudicial executions, enforced disappearances, torture and the protection of human rights while countering terrorism.

“We are particularly concerned by an apparently continuing pattern of death sentences handed out on the basis of evidence obtained through torture or ill treatment, often during a period of enforced disappearance,” they said.

Egyptian prosecution and judicial sources said verdicts in all cases were based on proof from investigations, confessions and forensic evidence, but courts did not rely on confessions they believed were a result of torture or coercion.

Speaking to Reuters on condition of anonymity, the sources said the U.N. statement constituted meddling in Egypt’s judicial affairs, and said death sentences had only been carried out after fair trials where the rights and defence of the accused were guaranteed in accordance with the law.

They also said that those who were convicted had committed crimes that resulted in the deaths of innocent people and threatened national stability and security – which are capital offences in Egypt.