Neither snow, nor rain, nor heat, nor gloom of night might keep letter carriers here from doing their jobs. Gunfire and aggressive dogs are something else again.

The U.S. Postal Service has temporarily suspended mail deliveries in some neighborhoods where letter carriers have faced real or implied violence.

"We've had rocks thrown at one of our vehicles, breaking the glass," said Sharon Adamczyk, secretary to Saginaw Postmaster Jacque S. Vican. "Our carriers get a lot of verbal abuse if they don't deliver [residents'] checks on the day they want it.

"Out of each six-day work week, our carriers are hearing gunshots on three of those days, on average," she said. "I'm not sure if they are contacting police each time they hear it, but about once a month we suspend mail delivery for the day when the gunfire is too close.

The Postal Service suspends delivery one block in each direction from the gunfire. "We have to protect our workers," Adamczyk told The Saginaw News.

In the most recent incident, carrier Nina Swan was shot in the back of the head Tuesday with a BB gun. Police arrested three males aged 12, 13 and 15 and confiscated two BB guns, Detective Sgt. Brent VanderHaar said.

Swan, 41, who said she saw two youths shooting real guns about three weeks earlier, had a severe headache for two days. Having been bitten on the thumb by a pit bull last summer, the 9-year veteran vowed not to return to the same route.

Saginaw isn't the only Michigan community where the Postal Service has halted deliveries to protect carriers.

Deliveries to a four-block area of northwest Detroit were suspended for about six weeks last spring because of loose dogs and staged dogfights. In Livingston County's Oceola Township, deliveries were halted for two days in August after pesky wasps repeatedly stung a carrier. The homeowners association hired an exterminator.