Horner, 51, was shot in the head near the site of a January 2014 Taliban suicide attack on a Lebanese restaurant in Kabul's affluent Wazir Akbar Khan neighborhood, according to news reports. The assailants shot him at close range and fled the scene.
Horner, a Hong Kong-based journalist who held both British and Swedish citizenship, was a reporter for Sveriges Radio, Sweden's national public broadcaster. At the time of the shooting, he was interviewing local security guards and was looking for a survivor of the attack on the Lebanese restaurant, the report said.
Horner had worked with Sveriges Radio since 2001 and had traveled to Afghanistan in the past, including to document the fall of the Taliban in 2001. He had also covered the Iraq War in 2003 and the Indian Ocean tsunami in 2004, according to Agence France-Presse.
The day after his death, news accounts reported that a Taliban splinter group, Feday-e-Mahaz, claimed responsibility for Horner's death. Its leader, Haji Najibullah, was also responsible for the 2008 kidnapping of New York Times' journalist David Rohde, The Nation reported. The group said in a statement that it had targeted Horner because he was a spy and not a journalist, reports said.
The Afghanistan Analysts Network, a research organization that works in Kabul and is funded by the Swedish and Norwegian governments, issued a report shortly after the killing that cast doubt on the claims put forward by Feday-e-Mahaz. AAN suggested the militant group was attempting to cash in on the publicity surrounding the high-profile attack on an international journalist in Kabul. AAN also suggested the possibility that Horner could have been killed as a result of any individual or local group wanting to "kill a foreigner."
Horner's death came less than a month before scheduled presidential elections to replace Hamid Karzai. In the weeks before his death, many foreigners who had freely traveled around Kabul had either chosen to limit their social activities or had been forced to do so by new security restrictions put in place by employers, the Times report said.