The family of Marie Colvin, the American journalist who died in Syria four years ago, is suing the regime of President Bashar al-Assad.
Relatives say they have evidence that she was murdered as part of a policy of deliberately killing journalists.
The wrongful death lawsuit was filed at a district court in Washington DC.
Colvin was reporting from the rebel-held area of Baba Amr, in Homs, in February 2012, when she was killed by government artillery.
Shortly before, she did live broadcasts for the BBC, Channel Four and CNN.
“I watched a little baby die today,” she said, talking over pictures of a child who had been hit by a sniper bullet. “That is happening over and over and over.”
She told the BBC that President Assad’s forces were “shelling with impunity, with merciless disregard for civilians”.
She told CNN it was “a complete and utter lie that they’re only going after terrorists… The Syrian army is simply shelling a city of cold, starving civilians”.
The Colvin family believes that the satellite phone used in these broadcasts was traced by Syrian intelligence and used to locate the Baba Amr media centre, where she was based.
According to documents obtained by their lawyers, a government informant then confirmed the location. An attack on the journalists was ordered that night, the lawsuit says.
“The transmissions were intercepted, and they were tracked to their GPS co-ordinates,” said one of the legal team, Scott Gilmore.
“On top of that there was a whole web of informants who were already out searching for the journalists. Any journalist in Homs… could have been a target”.
Marie’s photographer, Paul Conroy, had told the BBC shortly after the attack that the incoming rounds were “bracketed” on the media centre, meaning they were being deliberately targeted.
Conroy had served in an artillery regiment in the British Army.
“As an artilleryman, I think that was a good day’s work for a for a well-trained team. Nothing smacked of randomness in that situation,” he said.
Now the family’s lawyers say they have witnesses and documents smuggled out of Syria to prove this.
‘We know killers’
The lawsuit is the fruit of four years of research by the US-based Center for Justice and Accountability.
The documents are said to show that the artillery strike was approved or ordered by President Assad’s brother Maher, commander of the Republican Guards.