International support for a death row convict in America, including an appeal from UK journalist Don Hale, failed to persuade the authorities to overturn his sentence.

Don was asked to help very late on in the proceedings but Walter Mickens was executed by lethal injection in Virginia for stabbing a 17-year-old 143 times.

The former Matlock Mercury editor said: "It was rather sad but predicatable that Mickens would lose his last minute appeal for clemency.

"I am still rather surprised yet flattered by their interest and gave it one hundred per cent effort to try and persuade the authorities to agree a stay of execution."

The case has been labelled as one of America's most controversial, with defence lawyers describing the final verdict as 'one of the fastest-ever execution dates in modern history.'

Mickens' lawyer Kieron Johnson wrote to him after the execution to say: "Don, I want to thank you, once again, for all your help. Walter was overwhelmed by the level of public support for him."

Reuters reported: "Walter Mickens was executed by lethal injection on Wednesday for the 1992 slaying of a 17-year-old after Virginia Governor Mark Warner denied clemency pleas, including from two British legal societies.

"Mickens, whose case was reviewed by the US Supreme Court, was pronounced dead at 9:06 pm EDT."