WASHINGTON, Oct 19, 2021 (BSS/AFP) - The US capital Washington's much-

criticized metro network, the second busiest in the country, abruptly pulled
more than half of its trains from service on Monday following a derailment
that officials said could have been "catastrophic".

  "We apologize for this reduction in service and the inconvenience this is
causing our customers," the Washington Metropolitan Area Transit Authority
(Wmata) said on Twitter.

  The metro management took the dramatic step of cutting 60 percent of its
railcars under pressure from the National Transportation Safety Board, which
oversees US transport safety. Last week a railcar derailed, causing no
injuries but prompting the opening of an official investigation that
identified a design defect in train axles that had led to the incident.

  Inspectors identified no less than 39 cases of the same defect this year.

  The derailment "could have resulted in a catastrophic event," said NTSB
head Jennifer Homendy in a news conference Monday.

  The capital's metro, long criticized for its delays and chronic
malfunctions, is often cited as an emblem of how underinvestment affects
infrastructure in the United States.

  Overhauling the nation's infrastructure is a priority for President Joe
Biden, who is however struggling to rally Congress on the issue.

  The move will be a bitter pill for the hundreds of thousands of riders on
the subway, the busiest in the United States after New York's.

  The metro serves the federal capital and its suburbs spanning the states of
Virginia and Maryland.

  A total of 748 cars have been temporarily taken out of service pending a
decision by transport safety experts.