Missouri Gov. Jay Nixon is halting the execution of convicted killer Allen Nicklasson, citing concerns about the use of propofol as an execution drug.
The decision was announced Friday. Nixon also ordered the Missouri Department of Corrections to come up with a different way to perform lethal injections that does not include propofol.
Nicklasson's execution, scheduled for Oct. 23, had been set to be the country's first-ever using propofol.