Update (1:14 p.m.): The Arlington County Fire Department's Hazardous Materials Team tested the suspicious liquid at the Pentagon City Metro Station, and those tests came back negative, Capt. Gregg Karl told Patch.
"Our HazMat team declared them as a non-hazardous substance, and then turned everything over to Metro PD" at about 11:15 a.m., Karl said.
Metro spokesman Philip Stewart said the substance was still being tested as of 1:15 p.m.
Metro service continued as usual through the incident. Only a portion of one platform was cordoned off when the liquid was found, Stewart said.
Original story: The Arlington County Fire Department is investigating bottles of an unknown substance left outside the Pentagon City Metro Station.
The incident occured at about 10 a.m.
Fire officials are still on scene.
Further information is not immediately available, said spokesman Gregg Karl.
However, trains are still running their regular service and customers can come in and out of the station, said Washington Metropolitan Area Transit Authority spokeswoman Cathy Asato.