In the wee hours of Friday morning, as police hunted for the second suspect in the Boston Marathon bombings, Richard A. Davey, secretary of transportation, joined a conference call with Governor Deval Patrick and law enforcement officials. With a potentially armed suspect on the loose, an unprecedented decision was made: The region’s entire public transportation system was shuttered.
“We did not want to have customers potentially put in harm’s way,” Davey said. “And we didn’t want to give this suspect the opportunity to get out of the city using public transit.”
The closure of the MBTA was part of Patrick’s efforts to effectively lock down the region as law enforcement officers hunted for Dzhokhar A. Tsarnaev, one of the suspected Marathon bombers, who, after eluding authorities during a gun battle in Watertown, remained at large for much of the day. Portions of the transit system were reopened around 7 p.m.
The decision to close the T left tens of thousands of commuters unable to get to work or move around the city, turning Boston’s busiest neighborhoods into ghost towns.
At 5:30 a.m., a message went out on Twitter: “The MBTA is SUSPENDED on ALL modes until FURTHER NOTICE.” Alerts via text message and e-mail soon followed.
Still, the news came too late for many commuters, who arrived at stations around the city only to learn that there would be no service the entire day.
The decision to close the T came before any of the T’s subway trains left their stations. But about seven commuter rail trains had departed; they were halted and reversed, taking passengers back to their originating stop. Fifteen buses had begun their routes, and carried passengers through to the end of the route, then returned to garages.
Amtrak trains leaving from South Station were also halted. The Ride, the T’s paratransit service, canceled all its scheduled trips for Friday, and the commuter rail ferries were docked.
The closure drew comparisons to the shuttering of the New York City subway after the Sept. 11, 2001, attacks. Then, the Metropolitan Transportation Authority halted all subway trains when the World Trade Center towers crumbled, but part of the system was up and running again within a few hours.
The T has shut down in the past because of blizzards, hurricanes, fires, and floods. Several times, decades ago, labor strikes and a financial crisis also brought about one-day closures.
But, said Bradley H. Clarke, a transit historian, Friday was the only time the transit authority had chosen to institute an intentional, across-the-board shuttering of every sector of the T when the system was otherwise able to function.
“I would call this shutdown an unprecedented one,” Clarke said. “To shut down the whole system — buses, rapid transit lines, light rail lines, ferries — it’s very rare.”
Beverly A. Scott, general manager of the T, defended the decision to close all public transportation, saying officials could not take the chance of hampering law enforcement’s efforts apprehend to Tsarnaev.
“We’ve got to be able to isolate this guy,” Scott said early Friday.
Throughout the day, MBTA staff stood by at stations, waiting for word on when to restart the system, said Todd Johnson, director of the MBTA Operation Control Center.
“As you can imagine, to shut down a system as big and as vital as ours, it’s a hard decision. It’s a brave decision,” he said.
At the MBTA Operation Control Center in the Financial District, it was an eerie scene: More than a dozen screens displayed live video of the T’s busiest subway stations in the middle of the day, but all were vacant.
At South Station, more than a dozen police guarded the station, not even allowing passersby to walk on the sidewalk abutting the train terminal.
Courtney Rotolo, 22, a Boston College student, had been killing time at coffee shops close to the station since 6:30 a.m. as she waited to take a train to New Jersey. Suitcase in hand, she said she was unnerved by the mass closure.
“Everyone else is anxious,” Rotolo said, “so I was thinking, ‘Should I be anxious?’ ”
On his way to work Friday morning, Jonathan Cruz of Dorchester was stopped by an acquaintance who told him that JFK/UMass station, and the rest of the T, would be closed. Still, Cruz continued, hoping to get more information at the station.
He arrived at the station at about 6:30 a.m. and found no signs about service cancellation and no employees, he said.
“I think they should have put signs up but the problem is, we have the Internet and we watch TV all the time, so they thought we would know,” he said.
He questioned whether the closure was necessary to catch Tsarnaev.
“He’s hiding out in Watertown? Why is the whole system shut down?” said Deniz Alagoez of Dorchester. “I don’t get it.”Globe correspondent Gal Tziperman Lotan contributed to this report. Martine Powers can be reached at email@example.com. Follow her on Twitter @martinepowers.