New York commuters were reportedly unbothered by an apparent trail of blood-soaked newspapers snaking through a subway car on the city’s 7 train Thursday. Multiple witnesses claim riders went about business as usual before the car was evacuated for cleanup.

A tipster told Gothamist that after boarding the train car shortly after 9:00 a.m., they “noticed this trail of liquid and everyone sitting around it.” In two photographs emailed to Gothamist, a trail of what appears to be blood is soaked up with a string of newspapers before pooling by the car’s entrance. Soon after entering the car, the individual said the conductor checked in with everyone over the loudspeaker, and the train was cleared and taken out of service.

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Reached by Gothamist for comment, a spokesperson for the MTA confirmed that the southbound 7 train was taken out of service but could not confirm whether the liquid was blood. According to the spokesperson, “no medical treatment was given to any train riders.”

Another individual appeared to witness the same incident and wrote about the event on Twitter Thursday, noting in particular that the car's riders seemed unaffected.

“There is what appears to be a large puddle of blood covered up by newspapers on my train this morning,” Twitter user errin_jade wrote. “The craziest thing is that this has stopped no morning commuter from getting on this train car.”

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The user confirmed that the train was later evacuated, writing, “Welp. The entire 7 train was just cleared. Something about having to investigate this HUGE TRAIL OF BLOOD, which seems fair.”

As of Friday, there was no clear explanation about the what the substance was or from where it originated. A spokesperson for the MTA did not return International Business Times’ request for comment.