Washington (CNN) Many lawmakers, both Democratic and Republican, agreed one response to the deadliest mass shooting in modern US history should be to ban the sale of bump stocks -- but a month later, they are still legal and neither Congress nor the agency in charge of controlling such devices appear to be taking steps to outlaw them.

A bump fire stock, also known as a bump stock, is a device that enables semi-automatic rifles to fire more rapidly, similar to automatic weapons. Twelve of them were found on firearms recovered from the gunman's Las Vegas hotel room.

Gun control legislation has failed to make any progress in Congress after each mass shooting, and the Las Vegas massacre appears to be no different.

After the massacre, lawmakers first responded by saying they, including House Speaker Paul Ryan , didn't even know what a bump stock was.

Ryan then called for a regulatory fix for bump fire stocks earlier, rather than passing legislation that was proposed in the House and Senate.

"We think the regulatory fix is the smartest, quickest fix," he said when asked about how to address the devices.

Also in response at the time, nine Republican senators sent a letter to the Bureau of Alcohol, Tobacco, Firearms and Explosives asking the agency to review its policy on bump fire stock.

"We recognize that it is impossible to prevent tragedy and acts of 'pure evil,' in the words of our President," the senators wrote. "We believe, however, the tragic events in Las Vegas brought to light an issue from this past administration that we respectfully request that your Bureau swiftly review,"

After the shooting, the National Rifle Association pointed to the ATF to regulate the device.

"The ATF should review bump-fire stocks to ensure they comply with federal law," Jennifer Baker, spokeswoman for the Institute for Legislative Action at the NRA, told CNN, calling bills to ban them "intentionally overreaching."

But so far, there's been no change in the regulation of the device.

A spokeswoman for the ATF told CNN on Tuesday that Senate judiciary committee staffers were briefed by the ATF regarding bump stock related matters, but had nothing further to add.

When asked about the status of bump stock regulation on Tuesday, GOP Sen. John Thune's office referred to the letter, which he was part of sending -- but there appeared to be no new developments.

Stalled legislation

In the House, Republican Rep. Carlos Curbelo and Democratic Rep. Seth Moulton, introduced legislation to ban the sale of bump stocks, but there's been no action since.

And in the Senate, Democratic Sen. Dianne Feinstein introduced a bill that would ban the sale, transfer, importation, manufacture or possession of bump stocks, as well as trigger cranks and other accessories that accelerate a semi-automatic rifle's rate of fire.

GOP Sen. Ron Johnson was outspoken after the shooting about his support for banning bump stocks following the shooting. Asked for comment about the lack of action, his office only referred back to a statement he gave Politico for story published on October 4.

"Automatic weapons are illegal," he said at the time. "If that (bump stocks) facilitates that, to me it would be subject to the same ban. If that (bill banning bump stocks) actually gets on the Senate floor, I'd vote for it."

On Tuesday, Sen. Chris Murphy, a Democrat from Connecticut who has been engaged in the gun debate on Capitol Hill for years, told CNN that he's heard nothing on whether ATF is seriously looking at changing regulations surrounding bump stocks.

"I don't think the ATF is going to move unless the White House tells them to move and my impression is that they have been given no direction from the White House," Murphy said.

"It is unclear what the ATF can do," Murphy added.

GOP Sen. Lindsey Graham also told CNN he hadn't heard anything about where ATF is in reviewing bump stocks.

"I think once they make a decision then it would be our job to evaluate if it makes sense or not," Graham said.

Sen. Richard Blumenthal, a Democrat from Connecticut, told CNN that he thinks that the idea of a regulatory change is not enough, adding also he has not heard anything from the ATF on what they are doing now.

"We need legislation because the alternative is 'regulation,' which means two or three years of waiting for a rule that the NRA itself probably will challenge and tie it up for years more," he told CNN. "So I think the proposal for a rule or regulation is a deceptive dodge, purposefully suggested by the NRA as a way to avoid any real prohibition."

GOP Sen. John Barrasso told CNN that he hasn't heard what the ATF is doing about bump stocks now.

"I'm expecting to hear from them. I don't know that they're timeline is going to be, but It was something most of us hadn't heard of beforehand and then we found out how it came to be, we found out it was the ATF and we expect them to deal with it and let us know," Barrasso said.

Separately from the previous legislation, a bipartisan group of four House members, two from each major party, unveiled legislation Tuesday to regulate but not ban the sale of bump stocks. The "Closing the Bump Stock Loophole" act would require that those in "possession of or purchasing bump stock devices ... (undergo) a rigorous background check, fingerprinting and (pay) a $200 registration fee," according to a summary of the bill posted on the website of Pennsylvania Republican Rep. Brian Fitzpatrick.

CORRECTION: This story has been updated to correct Rep. Brian Fitzpatrick's party affiliation. He is a Republican.