HOUSTON (AP) — A federal judge has granted a request to delay this week's scheduled execution of a man condemned for fatally shooting a couple during a carjacking nearly 13 years ago.

The judge in Houston on Tuesday granted a stay for Dexter Johnson. His execution was slated for Thursday.

U.S. District Judge Alfred Bennett says he granted the delay in part over concerns of ineffective representation by Johnson's longtime appellate attorney, Patrick McCann.

McCann denies the claims, saying he has "never stopped working for" Johnson.

The 30-year-old Johnson was condemned for the June 2006 slayings in Houston of Maria Aparece and Huy Ngo that prosecutors say were part of a nearly monthlong crime rampage.

Johnson has long maintained he's innocent and has argued he can't be executed because he is intellectually disabled.