A 62-year-old great-grandmother in the United States has been executed at a prison in Texas.

Betty Lou Beets was killed by lethal injection after being convicted of murdering her fifth husband.

The last court to which she had the right to appeal, the US Supreme Court, rejected her case only about an hour before she died..

Then her final avenue of reprieve failed when Texas Governor George W Bush declined to intervene.

He said in a statement that, having reviewed the evidence, he agreed with the jury that she was guilty.

Mr Bush, who is seeking the Republican Party's presidential nomination, had the power as Texas governor to grant a 30-day stay of execution and ask the Board of Pardons and Paroles to re-examine the case.

But he has approved 120 executions as governor, including that of another woman, and has only intervened once.

Beets was also charged - but never tried for - killing her fourth husband. Prosecutors dubbed her the "Black Widow".

Her supporters maintained that she had been suffering from battered woman's syndrome, and that her case should be reviewed.

Beets' lawyers said there was evidence of emotional torment in all the relationships.

Beets had five children, nine grandchildren and six great-grandchildren.

She is only the second woman to be executed in Texas since 1863, and the fourth in the US since the Supreme Court lifted a national ban on the death penalty in 1976.

Life imprisonment

Beets' legal team, and a coalition of supporters which includes anti-domestic violence groups and Amnesty International USA, wanted her death sentence commuted to life in prison.

They said Beets, who had been in jail since 1985, was damaged psychologically and that she had poor legal counsel because the jury that sentenced her was not told about the alleged history of abuse.