ALBANY, N.Y. — New York state, Massachusetts and Maryland are suing Volkswagen and its affiliates Audi and Porsche over diesel emissions cheating, alleging that the German automakers defrauded customers, misled regulators and then sought to cover up the deception.

The lawsuits, announced Tuesday, allege that numerous employees and executives at Volkswagen knew that diesel vehicles had been equipped with software allowing them to cheat emissions testing, and that after regulators began investigating several employees tried to cover it up by eliminating data about the software.

“The allegations against Volkswagen, Audi and Porsche reveal a culture of deeply-rooted corporate arrogance, combined with a conscious disregard for the rule of law or the protection of public health and the environment,” said New York Attorney General Eric Schneiderman. “These suits should serve as a siren in every corporate board room, that if any company engages in this type of calculated and systematic illegality, we will bring the full force of the law – and seek the stiffest possible sanctions – to protect our citizens.”

In a statement, Volkswagen said it is already in talks with authorities regarding “a comprehensive national resolution of all remaining environmental issues arising from the diesel matter.” The company also noted that it has agreed to buy back or modify affected vehicles, create a $2.7 billion environmental trust and invest $2 billion on infrastructure for zero-emission vehicles.

“The allegations in complaints filed by certain states today are essentially not new and we have been addressing them in our discussions with U.S. federal and state authorities,” the company said. “It is regrettable that some states have decided to sue for environmental claims now, notwithstanding their prior support of this ongoing federal-state collaborative process.”

The legal action seeks “substantial penalties” that would be based on a calculation of the duration of the alleged violations.

While news of the rigged emissions tests first erupted a year ago, the new legal action makes several new allegations – most notably about the involvement of Volkswagen engineers and executives. The suit alleges that Volkswagen repeatedly submitted false emissions data to regulators and sought to eliminate evidence when an investigation began.

“This ‘clean diesel’ was nothing more than a dirty cover up,” said Massachusetts Attorney General Maura Healey. “Volkswagen acted as if it was above the law.”

Volkswagen also issued “sham” recall notices to some car owners and dealers in an effort to “turn down” the software, according to the New York lawsuit. Instead, some owners were told the recalls were needed for upgrades and “optimize” emissions.

At one point, when California regulators announced plans for emissions tests that threatened to expose the devices, the company’s top engineer emailed colleagues seeking help, according to the lawsuit, writing. “Come up with the story please!”

Just before the scandal broke, in August 2015, eight employees in the engineering department “promptly deleted or removed incriminating data about the devices from the company’s record,” according to the lawsuit.