Arkansas has become the first US state in 17 years to carry out back-to-back executions after putting two inmates to death within hours.

The southern state executed convicted killers Marcel Williams, 46, and 52-year-old Jack Jones on Tuesday.

Only last week Arkansas carried out its first execution in more than a decade.

Lendell Lee was put to death via lethal injection last Friday.

The 51-year-old, who had been on death row since 1993, was among eight men - including Jones and Williams - all scheduled to die before a lethal injection drug expires on April 30.

So far, Arkansas has carried out three of the killings, while four of the scheduled executions remain on hold.

The executions of Jones and Williams mark the first double execution in any US state since 2000.

Convicted killer Williams was pronounced dead at 10am local time, little more than three hours after Jones was put to death.

Jones was convicted of raping and killing Mary Phillips, 34, in 1995 and trying to murder her 11-year-old daughter.

He also was convicted of rape and murder in Florida.

Williams was convicted of the 1997 kidnapping, rape and murder of 22-year-old Stacy Errickson.

He also abducted and raped two other women.

After more than 20 years, justice has prevailed" for Errickson's family, Governor Asa Hutchinson said.