Lawyers in the US are preparing to challenge Ohio state's choice of death-penalty drugs after a convicted murderer took 26 minutes to die.

Dennis McGuire was executed on Wednesday after being convicted of the rape and murder of a pregnant woman in 1989. But lawyers say he died an agonising death from a new cocktail of chemicals - in violation of his constitutional rights.

Al Jazeera's Alan Fisher explains.

Source: Al Jazeera