FAIRFAX, Va. (AP) — President Barack Obama mocked conspiracy theorists and tore into the National Rifle Association for pushing “imaginary fiction,” as he described his plans to tighten gun control rules as modest first steps toward tackling gun violence in America.

In a prime-time, televised town hall meeting Thursday, Obama fielded tough questions from high-profile gun control opponents and supporters alike, often answering with sympathy and without confrontation as he tried to reassure Americans there is a middle ground on a fiercely divisive issue.

But Obama didn’t hold back when asked by CNN moderator Anderson Cooper about the notion that the federal government — and Obama in particular — wants to seize all firearms as a precursor to imposing martial law. He blamed that notion on the NRA and like-minded groups that convince its members that “somebody’s going to come grab your guns.”

“Yes, that is a conspiracy,” Obama said. “I’m only going to be here for another year. When would I have started on this enterprise?” Obama defended his support for the constitutional right to gun ownership while arguing it was consistent with his efforts to curb mass shootings. He said the NRA refused to acknowledge the government’s responsibility to make legal products safer, citing seatbelts and child-proof medicine bottles as examples.

Taking the stage at George Mason University, Obama accused the NRA of refusing to participate in the town hall despite having its headquarters nearby.

“Since this is a main reason they exist, you’d think that they’d be prepared to have a debate with the president,” Obama said.

 The plan has drawn intense criticism from gun rights groups that have accused the president of trampling on the Second Amendment and railroading Congress by taking action on his own without new laws. Just after his 2012 re-election, Obama pushed hard for a bipartisan gun control bill that collapsed in the Senate, ending any realistic prospects for a legislative solution in the near term.

Hennessey reported from Washington. Associated Press writers Josh Lederman in Washington and Jill Colvin in Burlington, Vermont, contributed to this report.