City advisory issued at 8:10 a.m.: "The City of Boston is urging City-wide shelter in place. As this investigation unfolds we are advising all residents, citywide, to shelter in place. Please understand we have an armed and dangerous person(s) still at large and police actively pursuing every lead in this active emergency event. Please be patient and use common sense until this person(s) are apprehended. We will continue to update the public with more information as it becomes available. All MBTA service remains suspended at this time."