Attorney General Matt Denn recently sent a cease-and desist letter to Defense Distributed ordering it not to allow access within Delaware to downloadable plans for a 3D gun that the company was planning to make available this week.

Denn also said he was exploring a lawsuit against the company.

In addition, Denn joined a coalition of 21 attorneys general urging U.S. Attorney General Jeff Sessions and U.S. Secretary of State Mike Pompeo to withdraw from the recent federal settlement that opened the door for the company to post plans online to print plastic guns using 3D printers, writing that these actions recklessly disregard public safety.

In his letter to the company, Denn said the availability of the plans for using a 3D printer to create an operation firearm poses a public safety threat to Delawareans.

“The state of Delaware Department of Justice will take legal action to prevent any effort by Defense Distributed intended to publish or offer individuals — including criminals — programs, codes, drawings or other sources of data that an individual can use to create untraceable firearms. Any such action constitutes a threat to public safety and a likely violation of our criminal law,” according to the letter. “A person who engages in conduct that is unlawful or unreasonable under the circumstances and who knowingly or recklessly creates or maintains a condition that endangers the health or safety of others, is guilty of criminal nuisance.”

The letter sent to Sessions and Pompeo by the group of state attorneys general expressed concern over the federal government’s recent settlement with Defense Distributed, which in 2013 was previously instructed by the U.S. Department of State to remove downloadable files for firearms from its website.

In the group letter, the attorneys general argue that publicly available information on 3D-printed weapons will enable the production of firearms that are untraceable and undetectable by magnetometers in places such as airports, government buildings and schools. Additionally, unrestricted access to this kind of information will increase illegal trafficking of weapons across state and national borders. The attorneys general also expressed their concern over the Department of State’s change in position on these matters, pointing to arguments the Department of Justice and Department of State have made for years in the challenge brought by Defense Distributed.

This multistate letter was organized by Attorney General Maura Healey, of Massachusetts, and includes attorneys general from California, Colorado, Connecticut, Delaware, the District of Columbia, Hawaii, Illinois, Iowa, Maine, Maryland, Minnesota, New Jersey, New Mexico, New York, Oregon, Pennsylvania, Rhode Island, Vermont, Virginia and Washington.