DENVER (AP) -- New ammunition limits and more background checks on firearm purchases will be under consideration as Colorado Democrats start pushing gun proposals after the mass shootings at an Aurora theater and a Connecticut elementary school.

The House Judiciary committee is expected to take its first votes on the proposals Tuesday. One bill would make it a crime to have or sell large-capacity gun magazines. Another proposal would require background checks on private gun sales.

Opponents have raised questions about how either proposal would be implemented.

The bills are part of a package of proposals Democrats announced last week. Democrats have already rejected Republican ideas to reduce gun violence, including a bill to allow school employees to carry concealed weapons.