Washington (AFP)

Target of recurring criticism, the Washington metro system abruptly withdrew from circulation on Monday morning more than half of its trains, following a derailment that could have had dramatic consequences.

"We apologize for the longer than expected waits," tweeted Monday the Washington Metropolitan Area Transit Authority (WMATA), the authority that made the sweeping decision under pressure from the US transportation safety office, the NTSB.

The potion promises to be bitter for the hundreds of thousands of users of this underground network, the busiest in the United States after New York, serving the federal capital and its suburbs spanning the states of Virginia and Maryland.

Last week, a one-row car derailed, causing no injuries, but justifying the opening of an official investigation.

This made it possible to identify a design defect in the axles, leading to derailments.

Inspections have identified no less than 39 examples of this defect this year, even if the cars of the trains concerned, manufactured by the Japanese company Kawasaki, are the most recent to equip the network.

The derailment "could have caused a catastrophic event," insisted Jennifer Homendy, the boss of the NTSB, in a press conference Monday.

In total, no less than 748 cars have been temporarily stopped, pending the outcome of additional expertise.

Criticized for its delays and chronic dysfunctions, the Washington metro is often cited as an emblematic example of underinvestment affecting the infrastructure sector in the United States.

A priority national project for President Joe Biden, who has not yet succeeded in passing his colossal bill on the subject.

The Washington metro had suffered a serious accident in January 2015: a train was found flooded with smoke, in a tunnel in the heart of the capital.

A woman was killed and more than 80 people were injured in this tragedy which had ended in ruining the reputation of the network.

© 2021 AFP