The only woman on federal death row in the US has been executed – a first in almost 70 years.
Convicted murderer Lisa Montgomery was put to death early on Wednesday, after the Supreme Court cleared the last obstacle to her execution by overturning a stay.
Montgomery's execution was the first time a woman has been executed since 1953 in the US.
She was pronounced dead at 1.31am Eastern Standard Time (6.31am GMT) on Wednesday, the Federal Bureau of Prisons said.
Montgomery was convicted in 2007 in Missouri for kidnapping and strangling Bobbie Jo Stinnett, then eight months pregnant. Montgomery cut Stinnett's foetus from the womb. The child survived.
Some of the victim's relatives travelled to witness Montgomery's execution, the Justice Department said.
Challenges were fought across several federal courts on whether to allow Montgomery's execution. She was initially scheduled to be put to death with a lethal injection of pentobarbital, a powerful barbiturate, on Tuesday in the Justice Department's execution chamber at its prison in Terre Haute, Indiana.
Montgomery's lawyer, Kelley Henry, called the execution a "vicious, unlawful and unnecessary exercise of authoritarian power," citing the condition of her client's mental state.
"No one can credibly dispute Mrs. Montgomery's long-standing debilitating mental disease – diagnosed and treated for the first time by the Bureau of Prisons' own doctors," Ms Henry said.
As the execution process began, asked by an executioner if she had any last words, Montgomery responded in a quiet, muffled "no," according to a reporter who served as a media witness.
Federal executions had been on hold for 17 years and only three men had been executed by the federal government since 1963 until the practice resumed last year under President Donald Trump, whose outspoken support for capital punishment long predates his entry into politics.
Montgomery's lawyers asked for Mr Trump's clemency last week, saying she committed her crime after a childhood in which she was abused and repeatedly raped by her stepfather and his friends, and so should instead face life in prison.
It is one of three executions the Department of Justice scheduled for the final full week of the outgoing administration.
Two other executions scheduled for Thursday and Friday have been delayed for the time being, by a federal judge in Washington, to allow the condemned murderers to recover from Covid-19.
The American Civil Liberties Union and some liberal lawmakers had previously opposed the government's plans to execute Montgomery, with the ACLU saying her life had been "marred by unthinkable trauma that resulted in documented brain damage and mental illness".
Montgomery's execution was the first of 2021 by the federal government and the 11th since last year.
In 2020, the US government executed 10 people. It was the first time that the federal government conducted more executions than all US states combined, according to a database compiled by the Death Penalty Information Centre.