Transcript for London terror attack eyewitness describes chaotic scene

James, thank you. Joining us now is mark Kindschuh, an American college student in a pub in borough market during the terror attack. Mark, thanks for being with us this morning. We're certainly flat that you're okay. But tell us what happened. You were sitting there with classmates. When did you notice something was wrong? Well, we had been sitting there, myself and about five of my classmates just eating for probably like 20, 25 minutes at most and all of a sudden we just heard really out of nowhere like four or five really loud successive gunshots and that's when everybody in the pub and we knew immediately something was wrong so everybody got down at once and went below their tables and got on the floor and then a wave of people who had been out on the street, maybe like about 30 people stormed in to see sanctuary or refuge and they all pushed their way towards the back of the pub. So I realized something was happening when the gunshots went off. That had to be a surreal moment when everyone came running in. Among the people who ran in was a man who was suffering a gunshot wound and I know you rushed in to help. Tell me what happened there. I picked my head up from where I was under my table with my classmates and just saw towards the front door just right off at the foot of the door a man just who had been pretty clearly injured badly with a pool of blood forming just next to his head. I got up and ran over to go see what I could do to help. And I know you took your belt off, you tried to put some pressure on the wound and then incredibly brave of you, you decided to go out of the pub to try and get help. I just couldn't sit there as this man was bleeding to death and just let it happen so I exited and told a member of S.W.A.T. Or of the police force who was right there about the fact that there was a man bleeding profusely from a head wound inside and at that point he just -- he acknowledged it and yelled at me to go back inside because the situation was still dangerous. And then when you got back inside I understand the bartender decided to lock the door but then tell me what happened next. The attackers were right outside the glass windows and the front door and were banging trying to get in apparently and then that's when -- when they were right outside is when eventually the S.W.A.T. Team was able to take him out. I want to ask you about how you feel today there in London and how londoners are reacting after such a horrific frightening weekend. Well, in terms of londoners, I don't think that there's really just walking around going to the grocery store, supermarket, I don't think there's really much of a difference, everyone is still out and about as they would be in any city just go about their daily live, the only sort of difference is there have been constant police sirens like over the past day and a half just because the counterterrorism services have been looking for the people who have connections to the attackers, so other than the police sirens going off a little more frequently than usual, everybody is going about their daily lives going to their jobs, so, yeah. A resilient city indeed and certainly again glad that you are safe. Thanks so much for joining us, mark. We appreciate it. My pleasure.

This transcript has been automatically generated and may not be 100% accurate.