It is normally closed to cars, to vehicles. but today it was closed to foot traffic done out of an abundance of caution. we should make that very clear. that is something that is sort of par for the course when there has been a breach of security in another state. that is something we would expect. i can tell you, rachel, at this hour, pennsylvania avenue is still closed down to foot traffic outside of the white house. and, again, president obama continues to monitor this situation. we expect him to receive briefs throughout the evening. rachel? kristen welker, thank you very much. nbc news white house correspondent. great to have that perspective. i want to bring in now from boylston street in boston, nbc s carey saunders who s out there in the cold. i understand police are still on the scene right now. what can you tell us about what things look like right there right now? reporter: well, it is is pretty much shut down. it will continue to be that way through into tomorrow. the r
massachusetts general hospital tonight where within the last hour trauma surgeons presiovide some details of the injured people who he has treated over the course of the day. there s a variety of injuries, probably the most common serious injuries are combined lower extremity injuries, combined meaning bone injuries, soft tissue injuries and vascular injuries to the lower extremities. we re seeing a lot of shrapnel injuries. many of those involve, again, predominantly the lower extremities. a lot of small metal debris. some people have asked already about whether these were bbs or parts of bombs. i just don t think we re able to say whether these are small bits of metal that were placed there intentionally or part of the environment. trauma surgeon explaining that there have been doctors in surgery since early this morning. he s been in surgery since 8:00 this morning. he s performed several surgeries on the injured victims of today s bombings. the bombings took place at
hour trauma surgeons presiovide some details of the injured people who he has treated over the course of the day. there s a variety of injuries, probably the most common serious injuries are combined lower extremity injuries, combined meaning bone injuries, soft tissue injuries and vascular injuries to the lower extremities. we re seeing a lot of shrapnel injuries. many of those involve, again, predominantly the lower extremities. a lot of small metal debris. some people have asked already about whether these were bbs or parts of bombs. i just don t think we re able to say whether these are small bits of metal that were placed there intentionally or part of the environment. trauma surgeon explaining that there have been doctors in surgery since early this morning. he s been in surgery since 8:00 this morning. he s performed several surgeries on the injured victims of today s bombings. the bombings took place at approximately 2:50 p.m. local time. the trauma surgeon report