President Barack Obama has promised to carry out a full investigation into the suspected US bombing of a hospital in Afghanistan that killed 19 people.

The US President says he extends his "deepest condolences", but the charity Medecines Sans Frontieres, which lost 12 aid workers in the blast, has called the airstrikes a violation of international law.

It's Director of Operations, Bart Janssens says the American military did know about the hospital.