THE parents of murdered journalist James Foley said they regarded an email they received from his captors last week as a hopeful sign they could negotiate with the Islamic militants.
Speaking on NBC's Today, John and Diane Foley from Rochester, New Hampshire, said they had last heard from the captors via several emails in December.
John Foley said he was excited to see the latest email, even though the kidnappers threatened to kill his son, because he hoped they would be willing to negotiate.
"I underestimated that point," he said of the threat. "I did not realise how brutal they were."
Foley (40) was kidnapped in Syria in November 2012. His Islamic State captors had demanded $132.5m (€100m) from his parents and political concessions from Washington. Authorities say neither obliged.
The militants revealed Foley's death in a video released on Tuesday. The extremists said they killed him in retaliation for US airstrikes targeting Islamic State positions in northern Iraq.
The Foleys said they had set up a special email address and sent multiple messages to try to engage the captors.
"We were just anxiously waiting," said Diane Foley.
GlobalPost, the Boston-based news organisation Foley contributed to, released a copy of the captors' final e-mail.
"Today our swords are unsheathed towards you, GOVERNMENT AND CITIZENS ALIKE!" they wrote. "AND WE WILL NOT STOP UNTIL WE QUENCH OUR THIRST FOR YOUR BLOOD."
In New Hampshire, Governor Maggie Hassan has directed that flags to fly at half-mast in honour of Foley tomorrow, the day a church service is planned in remembrance of him.
"An unconscionable act of terror took him from us far too soon, but his unyielding commitment to advancing our cherished First Amendment right across the globe and the truths he unveiled will live on for ever," she said in a statement.
Meanwhile, it emerged that Pope Francis has called Foley's parents.
The Vatican usually describes such personal calls by the pontiff as private without revealing the contents of the conversations. The Foleys declined to comment.
Foley was covering the fighting in Syria when he was abducted on Thanksgiving Day 2012. The 40-year-old journalist had not been seen until a video of his killing surfaced on Tuesday on the internet.
His murder began a new debate on the long-time US and British refusal to negotiate with terrorists, and Europe and the Persian Gulf's increasing willingness to pay ransoms.
The dilemma is how to save the lives of those kidnapped without financing terror groups, and encouraging more kidnappings.
By paying ransoms, governments in the Middle East and Europe have become some of the biggest financiers of terror groups.
By refusing to do likewise, the US and Britain are in the thankless position of putting their own citizens at a disadvantage.
Extremists called Foley's death a revenge killing for the 90 US airstrikes that have been launched against IS militants in northern Iraq since August 8.
But the ransom demands began late last year, even before the IS had begun its brutal march across much of western and northern Iraq.
"They don't need to do this for money," said Matthew Levitt, a counter-terror expert at the Washington Institute think tank. "When you ask for $132m for the release of one person, that suggests that you're either trying to make a point or you don't really need the money."
A senior Obama administration official said the IS had made a "range of requests" from the US for Foley's release, including changes in American policy in the Middle East.
State Department spokeswoman Marie Harf said the IS - which controls land across northern Syria and Iraq - has collected millions of dollars in ransoms so far this year alone.
"We do not make concessions to terrorists," she said. "We do not pay ransoms.
"The US government believes strongly that paying ransom to terrorists gives them a tool in the form of financing that helps them propagate what they're doing."