DES MOINES, IOWA (AP) -- An Iowa woman convicted in the drug-related slayings of three adults and two children near Mason City in 1993 is challenging her conviction and sentence.

Angela Johnson, of Forest City, was convicted in federal court in 2005 and sentenced to death for four of the killings.

She was given a life sentence in the fifth killing.

The victims were found buried in shallow graves in 2000.

Johnson was convicted in 2005.

The U.S. Supreme Court rejected Johnson's appeal last year.

Johnson has now filed a petition in U.S. District Court in Iowa for post-conviction relief, a constitutional challenge of her convictions and sentences.

Her attorney cites a dozen arguments, including ineffective council.

Johnson's boyfriend, Dustin Honken, was also convicted of the killings and sentenced to death.

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