A gun industry trade association filed a lawsuit Wednesday to block a requirement that dealers report sales of semiautomatic rifles to the federal firearms bureau.

The Obama administration announced the aggressive and controversial rules in July in hopes of curtailing gun-running to Mexican drug gangs.

The regulations would require about 8,500 dealers operating in the border states of California, Arizona, New Mexico and Texas to alert the Bureau of Alcohol, Tobacco, Firearms and Explosives about any person who buys two or more semiautomatic rifles greater than .22-caliber with detachable magazines within five days.

Slated to go into effect Aug. 14, the regulation has been fiercely opposed by gun groups, including the National Rifle Association.

On Wednesday, the National Shooting Sports Foundation — a trade group that represents gun manufacturers, distributors and retailers — filed the lawsuit in the District’s federal court seeking an injunction barring ATF from implementing the new rule.

In its court filing, the group argued that that ATF was exceeding its power in demanding such information from dealers. “This is the proverbial ‘slippery slope,’ and our industry is extremely concerned about it,” said Larry Keane, a senior vice president and general counsel for the trade association.

Scot L. Thomasson, a spokesman for ATF, said the agency will “vigorously defend its authority to collect information about multiple sales of certain rifles. . . in the four states along the southwest border.”

He said federal law allows the ATF to gather such information, and that courts have upheld that authority.

“The point of this request is to provide a targeted approach to address the problem of illegal gun trafficking through sales to “straw purchasers,” people who claim to be the true buyers of firearms but in reality are purchasing firearms on behalf of others, ” Thomasson said.

Officials with the Department of Justice, which is expected to fight the suit, have defended the regulations as a much-needed and legal tool to help them “detect and disrupt the illegal weapons trafficking networks.”