An 88-year-old man who is the world’s longest-serving death row inmate has been acquitted by a Japanese court.

Iwao Hakamada, who has been on death row for more than half a century, was found guilty in 1968 of killing his boss, the man’s wife and their two teenage children.

He was recently granted a retrial amid suspicions that investigators may have planted evidence that led to his conviction for quadruple murder.

The verdict brings to an end one of Japan’s longest and most famous legal sagas.

In 2014, Hakamada was released from jail and granted a retrial by a Japanese court, after defence lawyers showed that DNA from blood stains found on clothing alleged to have been worn by the killer did not match his own.

Since then he has been living under the care of his sister, due to his deteriorated mental state.

Prolonged legal proceedings meant that it took until last year for that retrial to begin – and until Thursday morning for the courts to declare whether Hakamada would be cleared of the charges, or hanged.

Hakamada is only the fifth death row inmate to be granted a retrial in the country’s post-war history.

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