ATLANTA (AP) _ Southern Bell has scaled back service at four drug-ridden housing projects, one of them so violent that mail is delivered under police escort.

''We've had folks flash guns and pull knives on our installers and threaten to use explosives on our vans. It's a compromise between providing service and protecting employees,'' said Doug Kendig, a telephone company spokesman.

Mail delivery to Bankhead Courts was suspended Saturday, when a letter carrier said he was caught near gunfire between suspected drug dealers. Service to the 450 apartments resumed Wednesday under police escort.

City Council President Marvin S. Arrington said Thursday that ''anarchy almost exists'' in the project. He said residents have attacked police officers and have not used an anonymous police hotline to report drug activity.

''I just don't think that people living in Bankhead Courts know exactly what they're doing to that community. They are going to become an enclave unto themselves,'' he said.

''I think it's unfair to ask people to put their lives on the line in these communities. We need to say to the residents, 'You are harming yourselves.'''

Kendig said Southern Bell has restricted installation and repair service, except for emergencies, to Monday mornings in Bankhead Courts and the Englewood, Gilbert Gardens and Jonesboro South apartments. Workers will enter in groups only.

Southern Bell made its decision two weeks ago after a female technician was harassed at Gilbert Gardens by six men who accused her of being a police officer, he said. One man drew a gun while the others rifled her van, Kendig said.

The woman was released when the resident whose phone she had repaired came outside and vouched for her, Kendig said.

Police Chief Morris Redding said Southern Bell was overreacting. ''We don't have any projects that people cannot move in and out of,'' he said.

''Bankhead Courts is not that bad. It's just got a reputation right now,'' said Gwen Scales, daughter of the tenant association president at the complex.