US condemns Syrian journalist's murder by IS in Turkey
The US has condemned the "vicious murder" of a Syrian journalist in Turkey by an Islamic State militant - the fourth such attack in a year.
Zahir al-Shurqat, a presenter for online TV channel Aleppo Today, was shot on a street in the south-eastern border town of Gazientep on Sunday.
The 36-year-old died in hospital two days later, Turkish media reported.
A US state department spokesman said Mr Shurqat had courageously worked to expose the "hypocrisy" of IS.
A prominent media advocacy group, the Committee to Protect Journalists, earlier called on the authorities in Turkey to ensure journalists can work safely throughout the country.
Mr Shurqat, who was from the IS-held town of al-Bab and regularly travelled to Syria to report on the fight against the jihadist group, was shot in the neck in broad daylight by a masked man, who fled the scene. He was taken to hospital and remained in a critical condition until his death on Tuesday.
The IS-linked Amaq news agency reported on Monday that the group had claimed it targeted Mr Shurqat in an "assassination operation".
Amaq's report also said IS militants had killed three people who had been working for the Syrian anti-IS activist group, Raqqa is Being Slaughtered Silently (RBSS), in Turkey over the past year. IS is believed to have only claimed one of the killings.
"Turkish authorities must urgently demonstrate that killing journalists on the streets of Turkey is unacceptable and will not go unpunished," Nina Ognianova of the CPJ said in a statement on Tuesday.
Since the beginning of the conflict in Syria five years ago, many Syrian journalists have crossed the border into Turkey, from where they have operated independent media outlets.
The CPJ said it had been told repeatedly by journalists that they faced restrictions on reporting on events inside Turkey and feared the Turkish government was not doing enough to protect them from threats emanating from Syria.
In December, Syrian activist and documentary maker Naji Jerf was shot dead in Gazientep. He and two RBSS activists, who were shot in the head and beheaded in the nearby city of Sanliurfa in October, had appealed to the Turkish police after receiving death threats, friends and fellow activists told the Reuters news agency.
"We stand ready to support Turkey as it works to bring to justice those responsible for attacks on the media," US state department spokesman John Kirby said, using an acronym based on the previous name of IS in Arabic.
"Freedom of the press, including ensuring that journalists can safely report on the crisis in Syria, remains critical as reporters keep working to expose the truth about this brutal conflict and Daesh's atrocities," he added.