UPDATE 4:34 p.m. EDT: ABC News reported Metro-North has restored limited service after the East Harlem explosion Wednesday morning. Two of the four tracks near the structure, the ones that were farthest away from the collapsed buildings, were restored after the debris was cleared.

Original story: 

After an explosion at two buildings in East Harlem Wednesday morning, Metro-North suspended service out of Grand Central Station, and hours later CBS New York reported the service would be terminated “indefinitely.” As a result, an alternative service plan has been provided by the Metropolitan Transportation Authority for commuters who rely on Metro-North.

The MTA said the New York City subway will honor Metro-North tickets. Manhattan-bound trains are stopping at stations in the Bronx, where passengers can then transfer to the subway. Those who are traveling north should take the subway to the Bronx to connect to the provided trains.

According to the New York Daily News, the MTA said the 4, 5, and 6 trains were running at slower speeds due to concerns regarding “vibrations” from the blast. It’s not known when Metro-North service will resume, but all the debris must be removed from the tracks and signals and other equipment has to be inspected, MTA spokesman Sal Arena told the paper.

“We hope to have service restored as soon as we can, but we won’t restore service until we’re certain that the tracks in that area are safe,” MTA spokesman Aaron Donovan told WCBS 880 on Wednesday via CBS New York. Click here to view the service alternatives for the Harlem Line & New Haven Line and Hudson Line.

The East Harlem explosion reportedly sent “people flying out of window,” killing two women, witnesses told the New York Daily News. Hours after the building collapsed, a reported 12 people are still missing.

New York City Mayor Bill de Blasio said the explosion that destroyed the buildings was "based on a gas leak." The mayor added: "This is a tragedy of the worst kind because there was no indication in time to save people.”

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