(David Goldman/AP)

Managers at some U.S Postal Service branches are reportedly asking mail carriers to return from their routes without always completing their deliveries because of concerns about overtime costs and safety.

ABC affiliate WJLA first reported on Wednesday that a postal station in Northwest D.C. was forcing its workers off the streets at certain hours to avoid overtime. The story quoted an anonymous employee saying “they’re constantly telling us to leave first-class mail, leave packages, everything, and it’s getting ridiculous.”

Several Northwest D.C. residents also complained about customer service in the report, saying they could no longer rely on the Postal Service for timely and accurate mail delivery.

USPS spokeswoman Sue Brennan said Thursday that the agency had instructed its carriers last week to be off the streets by 6 p.m. because of weather-related safety concerns after a severe winter storm hit the region.

“This was a unique event,” Brennan said. “As a rule it is not Postal Service policy, nationally or in Washington, D.C., that carriers are to return to the office at 6 p.m. regardless of whether or not their routes have been completed.”

National Association of Postal Supervisors president Louis Atkins said Thursday that some postal managers are trying to keep carriers off the streets at night to avoid potential violence. He said stations in D.C., Miami and Seattle have taken that step.

“Bringing [the carriers] in before dark is something we can control that has a significant effect on violence at night,” Atkins said. “You can’t stop it all, but you can do your part.”

Nighttime violence against on-duty postal workers is a growing concern for USPS employees. In November, a D.C. postal worker Tyson Barnette was fatally shot while working a new route in Prince George’s County that often kept him out until 7 p.m.

MORE: Postal worker’s death raises concerns over late deliveries

Atkins said the Postal Service could ensure that all routes are completed before nightfall by requiring employees to start work earlier and hiring more personnel to literally help carry the load.

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