GRAPEVINE — Screeners are being unfairly blamed for failures to detect weapons and explosives at airport security checkpoints, the head of the Transportation Security Administration said.

So-called human failures often were the result of government watchdogs intentionally loading the bags a certain way into the machines to exploit the equipment's limitations, TSA Administrator David Stone said Saturday during a visit to Dallas-Fort Worth International Airport.

Safety chief says airport screeners unfairly blamed, continued