DENVER - People packed the Colorado State Capitol for gun control hearings Monday.

The twitter account @ColoSenGOP tweeted a picture of crowds filling the Capitol building Monday morning with the caption: "People lined up to testify at the State Capitol today about the Democrat gun control proposals."

Ryan Parker (‏@ryanparkerdp) with the Denver Post tweeted a photo of a Magpul vehicle outside the Capitol with the caption: "A few of the cars in the Capitol's parking lot."

Magpul is an Erie-based company that manufactures firearm accessories.  Magpul has said it will leave the state if lawmakers pass a bill to ban magazines that hold more than 15 rounds.

Lawmakers have tried to ease Erie-based Magpul Industries' concerns by amending the proposal to specify the company can still manufacture magazines of any size, but they could only sell them out of state or to law enforcement and the military.

A plane circled above the Capitol Monday towing a sign that read, "Hick, do not take away our guns!"

Lawmakers are also hearing emotional testimony from people affected by gun violence.

"We need to stop this madness," said Dave Hoover, uncle of an Aurora movie theater victim.

Mark Kelly, the husband of former Arizona Rep. Gabby Giffords, was scheduled to testify in at least one hearing on gun control bills Monday in Denver.