The US president is in the Situation Room along with the chairman of the Joint Chiefs of Staff and they are monitoring the information coming in, in terms of the security situation, the details of the explosion, the details of the casualties. US media have been reporting that a number of US personnel have been injured.
The president last week had started publicly warning about the threat of an attack, which he said might come from IS-K, the Afghanistan branch of the Islamic State group - and that is one of the main reasons we understand why he didn't want to extend the deadline of the evacuation.