WASHINGTON (AP) — Union leaders say emergency responders are still having communication problems in Washington subway tunnels in the wake of a fatal accident on the system last month.

District of Columbia firefighters’ union president Ed Smith and emergency medical workers’ union president Kenneth Lyons discussed the ongoing issues on Thursday during a D.C. Council hearing on the accident.

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Smith says firefighters’ radios wouldn’t necessarily work in the tunnels if something else went wrong. Lyons says emergency workers would be better off using cellphones.

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One passenger was killed and more than 80 others were taken to hospitals with smoke inhalation after a train filled with smoke in a tunnel near a downtown station. The National Transportation Safety Board says an electrical malfunction led to the smoke and is investigating the cause.

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