Graham, who protested his innocence throughout his 19 years on death row, fought every step of the way to the execution chamber, where he was given a lethal injection.

Guards had to subdue him when they came to take him from a holding cell a few feet away at 8.20 pm on Thursday evening, after a last ditch attempt by his legal team to win a stay of execution failed.

His last words were: "The truth will come out . . . They are killing me tonight. They are murdering me."

According to witnesses he died with one eye shut and one eye open, staring at the Rev Jesse Jackson, the civil rights leader, whom he had invited to be present.

Bianca Jagger, representing Amnesty International, was also present, as was the grandson of Bobby Lambert, for whose 1981 murder he was convicted.

Graham admitted a string of armed robberies in the week after the murder, but denied shooting Lambert. There was no scientific evidence against him and he was convicted on the testimony of a sole witness.

Witnesses who said Graham did not resemble the killer were not called.

The French foreign ministry spokeswoman, Anne Gazeau-Secret, said the French consul in Houston, speaking for all 15 EU states, had tried to intervene, but the Texas governor, George W Bush, had ignored the appeal for clemency.

"We are dismayed by the execution," she said. "We especially regret that the authorities in Texas knowingly took the risk of putting an innocent man to death. We will make the campaign for a moratorium on executions in the US one of the themes of our presidency of the EU."

Mary Robinson, the UN high commissioner for human rights, said the execution "ran counter to widely accepted international principles".

© Guardian Newspapers Limited 2000

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