03/08/2012 08:26 am ET Updated Mar 08, 2012

Metro Riders Report Fishy Odor At Downtown Rail Stations

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WASHINGTON -- Metro is investigating another peculiar odor, and it's not a pleasant one like the sweet mysterious "maple syrup" smell that has been known to waft over parts of New York City from New Jersey.

As WRC-TV/NBC4 reports, riders on Wednesday evening started reporting smelling something foul at Orange and Blue line stations downtown.

The odor, described as "dead fish," "rotten fish," "rotten seafood" or something from a "pet store," was evident at stations like Foggy Bottom-GWU, Metro Center, Farragut West and L'Enfant Plaza, according to Twitter:

So, what was the smell?

A Metro employee told the television station that organic brake pads may be a culprit, though an agency spokesman would not confirm that until the odor could be investigated further.

In January, when a similar smell fouled some stations, like Gallery Place-Chinatown, a Metro spokesman said it was sewer gas and not organic brake pads.

Smelly brake pads are not a new issue for Metro.

In 2006, a Metro spokesman pinpointed a foul odor on new brake pads installed on 5000-series rail cars, according to a The Washington Post report at the time.