The photos in the blog post certainly were eye-catching — four pictures said to be a broken friction ring from a Metrorail car.

The pictures on unsuckdcmetro’s blog, posted Tuesday, were said to come from a source.

Metro chief spokesman Dan Stessel wouldn’t comment on the pictures. He said the two incidents are under investigation as to what caused the friction rings to come off.

In the past three weeks, Metro has had incidents were friction rings — part of the brake assembly system on rail cars — have come off on two separate trains.

One incident happened Jan. 6, where a friction ring came off a train on the Orange Line.

Last weekend, Metro said it completed inspections of brake assemblies on 464 rail cars in the 2000- , 3000- and 4000-series rail cars.

Metro said it took “the precaution of replacing more than 290 friction rings from brake assemblies that are showing wear.” They said that effort “exceeded the standards set by the original equipment manufacturer.”

On Dec. 20, a friction ring fell from a 5000-series rail car, damaged two more rail cars and shut down service along the downtown core of the Orange and Blue line for hours and trapped riders on trains.

Stessel has said the two incidents “involve different designs and different manufacturers.”

In the photos unsuckdcmetro posted, the friction rings were said to be “found Friday morning on car 3273 at Shady Grove” during a “daily safety test and external visual inspection during which there was emphasis on looking for things like this,” according to the blog’s source.

The source said his “best guess as to what’s going on is that Metro got a batch of bad parts.”

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