Saturday’s failed test of a North Korean ballistic missile prompted subway company Tokyo Metro to briefly halt its train lines as a precaution, but criticism has since grown that it overreacted.

On Saturday morning, the private railway shut down all of its train lines for about 10 minutes in response to news that the North had launched a missile. It resumed operations after receiving no further update, spokesman Noboru Ishikawa said.

This was the first time Tokyo Metro had ever taken such a safety precaution, Ishikawa said, adding that the discussions on the emergency measures were held in mid-April.

Saturday’s stoppage, which affected about 13,000 passengers, was ordered in accordance with the consensus reached at the meeting, he said.

Although subways are generally considered safer from missile attack than transportation above ground, the measure is nonetheless necessary to let trains temporarily stop at nearby stations so passengers can evacuate, Ishikawa said.

The last thing the firm wants, he said, is to have passengers stranded in the middle of dark tunnels deep under the streets of Tokyo.

But soon after the news broke that Tokyo Metro went so far as to halt the trains, passengers and others took to social media to express bewilderment over what they saw as an overreaction.

“I was just using a subway and they announced that all trains have been shut down due to North Korea’s missile launch . . . I couldn’t believe what I just heard,” Twitter user @nogi_ur46maiyan said.

“North Korea’s missile launch, which failed, caused Tokyo Metro to stop operations, but at other railway companies it was business as usual. So are subways in Seoul. What the hell,” user @singlikehug said.

The Dong-A Ilbo, a leading newspaper in Seoul, covered Tokyo Metro’s unusual step in its online edition, calling it “fussy” in a headline.

West Japan Railway Co. (JR West) reacted to the test as well, temporarily halting bullet trains running along the Sea of Japan, which separates Japan from mainland Asia.

Like Tokyo Metro, JR West called a meeting at the end of April to debate what to do should North Korean missiles be fired in response to “escalating tensions” on the Korean Peninsula, according to a spokesman who refused to be identified due to internal policy. But the other railways remained largely unfazed, including Central Japan Railway Co. (JR Tokai).

A JR Tokai spokesman, who declined to be named per internal policy, said the firm determined there was no need to suspend operations because J-Alert, the government’s satellite-based warning system for missile crises and natural disasters, issued no warning about the launch.

The spokesman said JR Tokai’s policy is to weigh the option of stopping trains only after J-Alert is activated, setting it apart from Tokyo Metro, which acted in response to a media report.

Ishikawa, the Tokyo Metro spokesman, said that, from now on, the company will initiate a system-wide halt only when a J-Alert warning is issued.

Koichi Oizumi, a professor of crisis management studies at Aomori Chuo Gakuin University, said Tokyo Metro’s response to the news alert was all in all premature, and that it should have weighed more carefully the tremendous impact such a disruption could have on people’s lives and the economy.

“But more importantly, there should be a nationally standardized guideline on how railway companies should act in the event of such an emergency. . . . You may have to wonder why JR trains, which are more susceptible to the danger of a missile, continued their business as usual while the subway stopped,” he said.