Transcript for 3 US soldiers killed, 1 wounded in insider attack in Afghanistan

We'll move on to a deadly attack on American soldiers overseas. U.S. Officials say an Afghan army soldier who is being trained by our troops turned on them opening fire. ABC's Stephanie Ramos is in Washington with who is claiming responsibility for this attack. Good morning, Stephanie. Reporter: Dan and Paula, good morning. The Taliban did not waste any time claiming responsibility for this attack. Incidents like these have gone down in recent years, but this shooting rampage is bound to influence how president trump and his national security team respond to the fight in Afghanistan. American soldiers ambushed in a deadly insider attack in eastern Afghanistan. According to Pentagon officials an Afghan army soldier aimed his weapon on U.S. Service members there to train him as part of the train, advise and assist mission. Three U.S. Army soldiers killed. One more wounded. The Taliban says they're responsible releasing this photo of the alleged attacker who was killed. If you look at the number of insider attacks since the U.S. Has been in Afghanistan, many of these attacks have come from people who have lived or been recruited from the eastern provinces which are up next to $% Pakistan which is traditional Taliban home territory. Reporter: The attack in the same province where the U.S. Dropped its most powerful nonnuclear bomb on ISIS targets in April. President trump and vice president pence were briefed immediately. When heroes fall, Americans grieve and our thoughts and prayers are with the families of these American heroes. Reporter: This insider attack typically called a green on blue attack is the deadliest in more than a year and Afghan soldiers, they're also at risk of being targeted by who they think are comrades. Dan and Paula. So sad for those fallen soldiers. Stephanie, thank you.

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