Publicly announcing that US intelligence agencies “underestimated” the presence and activity of Islamic State militants in Syria, US President Barack Obama in an interview with CBS called the country a “ground zero” for international jihadists.

“Over the past couple of years, during the chaos of the Syrian civil war, where essentially you have huge swaths of the country that are completely ungoverned, they were able to reconstitute themselves and take advantage of that chaos,” Obama said in an interview made on Friday but aired on Sunday.