she was captured more than a year ago and was also an aid worker trying to help syrians caught in the country's brutal civil war. meanwhile, nbc news foreign correspondent ayman mohyeldin knew peter and had lunch with him weeks before he was captured in eastern syria. >> he was a great guy. very calm. a person who is driven by great sense of ideals after several years of questioning all that was happening around him in the middle east, he felt, finally, he had a purpose in trying to help the syrian refugee. >> more on the execution of kassig richard engel reports from turkey. >> unfortunately a graphic 16 minute video released by isis has been awe then candidated. we will not be showing it here. no need to spread the group's propaganda. peter was the fifth western hostage murdered and the third american. at the vigil in indianapolis, friends, supporters, and peter