Gwinnett County officials will soon begin to mail warnings to motorists who drive past school buses stopped to pick up or drop off students.

The school system has placed cameras alongside 71 buses and eventually plans to have them on about 300 buses as part of a new program. Officials will begin sending warnings to motorists recorded driving past the stop signs on school buses in a few weeks. Violators will receive fines ranging from $300 for the first offense to $1,000 for three or more offenses once the program is fully in place in January.

“We are doing this to prevent a possible tragedy,” Gwinnett school system spokeswoman Sloan Roach told reporters at a press conference Thursday to unveil the cameras.

Gwinnett has hired Arizona-based Redflex Traffic Systems to install the cameras. The company will receive 50 percent of money collected in fines. The Gwinnett school system and county government will split the rest, Roach said.

Redflex has a five-year contract with Gwinnett to install and manage the cameras. Gwinnett officials said the contract will be reviewed annually.