US President Obama defends hostage Kayla Mueller response

President Barack Obama has rejected the suggestion that the US could have done more to free aid worker Kayla Mueller, following confirmation of her death.

Ms Mueller, 26, was abducted while working in Aleppo, Syria in 2013, and held by Islamic State.

Speaking to BuzzFeed News, Mr Obama paid tribute to Ms Mueller and said that the government had "devoted enormous resources" into trying to free her.