The family of an American journalist is suing the Syrian government over her death.

Marie Colvin was working for The Sunday Times when she travelled to Syria in February 2012 to cover the seige of Homs.

At the time, the Syrian city was under rebel control and civilians were suffering badly due to tactics used by Syrian president Bashar al Assad.

Her relatives say they have evidence that she was "hunted down" as part of a policy of deliberately killing journalists.

The lawsuit has been filed in US District Court on behalf of of Ms Colvin's sister Cathleen Colvin and other family members.

Lawyer for the case Scott Gilmore said: "Marie Colvin was killed for exposing the Assad regime's slaughter of innocent civilians to the world.

"The regime wanted to wage a war without witness against democratic opposition. To do that, they needed to neutralise the media."

The day before her death Ms Colvin had told CNN that it was a "complete and utter lie" that the Syrian army were only targeting terrorists. She has said they were "simply shelling a city of cold, starving civilians".

In a report to the Sunday Times she had explained the effect the shellings were having on the people of Homs.

French photographer Remi Ochlik who also died in the attack | Julien de Rosa / AP/Press Association Images

On February 21st, an informant's tip led Syrian military intelligence to her location and the following morning, Syrian artillery fired on the building, killing her and French photographer Remi Ochlik.

British photographer Paul Conroy and Syrian interpreter Wael al Omar suffered injuries in the attack.

Director of the Center for Justice and Accountability, who filed the case on her relatives behalf said: "This is the first war crimes case against the Assad regime - but it won't be the last."

Dixon Osburn added: "Building a lasting peace in Syria will require accountability for those on all sides of the conflict who are responsible for atrocities."

The lawsuit is filed under a federal law allowing victims to sue designated state sponsors of terrorism for the murder of US citizens.

Ms Colvin, a 25-year veteran of war coverage, and Mr Ochlik are among more than 200 journalists killed in Syria since March 2011.

Additional reporting by IRN