UK & World News
US Vows To 'Degrade And Destroy' Islamic State
Barack Obama has vowed that justice will be done against the Islamic State after it beheaded a second American journalist.
The US President said America would "not be intimidated" by IS violence and promised to "degrade and destroy" its forces.
He spoke after a video was released apparently showing a masked IS militant killing US reporter Steven Sotloff - and warning that a British hostage will be next.
The 31-year-old, from Florida, is seen dressed in an orange jumpsuit in the video - titled A Second Message To America.
Mr Sotloff, who had worked for Time and Foreign Policy magazines, was forced to read out a statement before he was killed.
Intelligence officials believe the killer is the same British man who murdered journalist James Foley on video two weeks ago.
Sky News is not naming the British captive - who is shown kneeling at knifepoint - at the request of his family.
Earlier, the UK Government's emergency committee met to discuss the threat, with Prime Minister David Cameron saying Britain will not be "cowed" by "barbaric killers".
The US and UK have both said the video showing Mr Sotloff's murder is authentic.
Mr Sotloff's relatives said they were aware of "this horrific tragedy" and were "grieving privately".
Israel also revealed he had dual citizenship and it withheld the information to protect him.
Mr Obama told a news conference in Estonia: "We will not be intimidated. Their horrific acts only unite us as a country and stiffen our resolve to take the fight against these terrorists.
"Those who make the mistake of harming Americans will learn that we will not forget, our reach is long and that justice will be served."
Hours after the video emerged, Mr Obama authorised a State Department request for 350 extra US military troops to be stationed in Iraq.
The White House said the troops would "protect our diplomatic facilities and personnel in Baghdad".
Nato leaders are set to attend a two-day summit in Newport, Wales, on Thursday.
The group will discuss offering training support to the Iraqi military to combat IS fighters, according to Sky News sources.