Editor’s note: This story has been updated to reflect recent events in the case.

The ripple effects of Boston’s terrible week reached far and wide.

With an ongoing investigation in the days following Monday’s deadly Boston Marathon bombing, the city was already on edge. But on Friday morning, as law enforcement engaged in a full-throttle manhunt for the surviving suspect, the city took an unprecedented step, shutting down transportation systems and ordering local residents to “shelter in place.”

(On Friday evening, shortly before the suspect in the case was captured, the “shelter in place” order was lifted.)

Conferences and association events underway or about to begin in Boston felt the effects. More details:

Meetings disrupted: The Massachusetts Convention Center Authority (MCCA) announced Friday morning that events already in progress at the Boston Convention & Exhibition Center and the John B. Hynes Veterans Memorial Convention Center would continue, but move-out work affecting the Ambulatory Surgery Center Association (ASCA) and move-in for Boston Comic Con were delayed. “Attendees, exhibitors already in the building should stay and continue with scheduled activities,” James E. Rooney, MCCA’s executive director, said in a statement. “Attendees in route to the buildings for scheduled events will be allowed access, but should be prepared for vigorous security screening.” The MCCA asked those not already in transit, including those planning to attend the Experimental Biology 2013 conference, scheduled to begin Monday, to stay home.

Still happening: ASCA chose to continue its annual meeting at the Hynes Convention Center after much debate and a meeting with its board, making its announcement prior to the city shutdown. “As we have learned all too often in recent years, we are a resilient people when faced with tragic events like [Monday’s],” the group wrote in a statement on the event’s website. “Please keep all the victims of the attack in your thoughts in the coming days as our law enforcement officials find those responsible for this horrendous crime.” Despite the shutdown, the event continued Friday, with the #ASCAconf hashtag remaining active.

Ground travel challenges: While Boston’s Logan International Airport remained up and running, other forms of mass transit proved a challenge to tradeshow attendees. Massachusetts Bay Transportation Authority suspended all forms of transit—including trains and buses—with the exception of the silver line, which leads from Logan Airport to downtown. Highways remained open, but regional bus companies—including Greyhound, Megabus, and Bolt Bus—suspended operations in the area and refunded customers. While taxis ran locally, there were very long lines at Logan and passengers were being asked to share rides, according to the Associated Press. (After the “shelter in place” order was lifted Friday, transportation resumed, including on Amtrak, which returned to a normal Saturday schedule.)

Could shutdowns be a trend? The decision to lock down a city the size of Boston may be unprecedented, but the trend of shutting down in emergency situations is growing (particularly in cases of shootings or terror attacks, but also in bad weather), as Quartz reports. It’s seen as safer to shut down than to risk endangerment or damage. The Strategic Policy Partnership’s Robert Wasserman told the publication that choosing not to shut things down in the case of an emergency “puts the public at risk and we have learned that we have a responsibility to prevent further injury to the public, not just because it is difficult for a person on the run to hide,” he said. For associations, that may mean ensuring that a backup plan is in place in case of last-second emergencies.

Boston's Downtown Crossing, empty at 10:30 a.m. as a result of a city shutdown on Friday. (photo by @WBURSteve)