 Officials in Afghanistan have now confirmed at least 30 people died in an attack on the country's largest military hospital in the capital, Kabul. Four men, at least one, wearing a suicide jacket were involved. The so-called Islamic State group has said it carried out the attack. The first time IS fighters have engaged with Afghan security forces in the capital, perhaps suggests the group is changing tactics. Let's speak now to Colin Cookman. He's a South and Central Asia analyst at the United States Institute of Peace is in Washington, D.C. Colin, what do you make of this attack? Well obviously it was a horrible morning in Kabul in terms of the casualties. We've seen a few attacks by the Islamic State in Kabul over the past several months, but as you said this is the first one where they've sort of engaged in a battle with Afghan forces. But as they've come under pressure in the eastern part of the country it seems perhaps the strategy is shifting on their part and they are now relying more on these major large scale attacks. So do you see it as a sign of strength or a sign of weakness? And do you see it as a change of tactics? It does seem to be a change of tactics in terms of the strength of the organization overall. Reports from U.S. and NATO military commanders suggest that they are under greater pressure in the east. There are a number of fighters in the country declining. So this would be potentially a way that they're trying to respond to put a hit back against the Afghan government. Does it surprise you at all that security at the hospital wasn't tighter? Would it have been seen as a likely target? Well I can't speak to sort of the details of the security protocols there. I think obviously this particular hospital did come under attack in the past by the Taliban actually several years ago. But there's been a number of these attacks in Kabul. Unfortunately a couple of gunmen and a suicide bomber is enough to tie up the situation for several hours as the Afghan security forces work to respond. What are the chances do you think of the Afghan security forces getting a grip on the country as a whole? Senior U.S. military figure described the war there as lost today. Well obviously it's a major challenge for the government. Last spring and summer there were intense Taliban attacks around the country as well as groups like the Islamic State. U.S. and other partners are working to support those forces. But looking into the spring and summer ahead I think we can expect that it will also be a serious challenge for them to defend against these sorts of attacks and to take more proactive action against these groups. Colin Cookman of the U.S. Institute of Peace, thank you very much. Thank you.