New York City Mayor Michael Bloomberg waits to speak at a gun violence summit at Johns Hopkins Bloomberg School of Public Health in Baltimore. Sitting alongside Bloomberg is Maryland Gov. Martin O'Malley. (AP Photo/Patrick Semansky)

Maryland Gov. Martin O’Malley (D) argued Monday that gun-control measures are an essential part of any “common-sense” response to last month’s school shootings in Connecticut, as he appeared with New York Mayor Michael R. Bloomberg (I) at a high-profile policy summit in Baltimore.

“We know that it makes absolutely no sense when you look at the level of carnage on our streets from guns, to blame every factor but guns,” said O’Malley, who plans to formally unveil a legislative package on gun violence later this week. “If we’re going to have a comprehensive approach, well, let us be comprehensive.”

O’Malley and Bloomberg, one of the nation’s leading gun-control advocates, were among the first speakers at the gathering hosted by the Johns Hopkins Bloomberg School of Public Health. The school is named for the New York mayor, a Hopkins graduate and major donor to the university.

The two-day summit, pulled together in the wake of the Newtown massacre, features more than 20 experts on gun policy and violence. Organizers said they plan to publish a book based on the event that will be available to members of Congress within two weeks as they debate reforms on the federal level.

O’Malley’s forthcoming proposal — which was detailed in a Washington Post story published Monday — will include an assault weapons ban and some of the nation’s strictest gun-licensing requirements, as well as measures geared toward improving mental health services and school safety.

“There is a sickness in our country, and that sickness is gun violence,” O’Malley said.

Critics of O’Malley’s approach have argued that the gun-control measures would have done nothing to stop the shooter in Newtown and that policymakers should focus on school safety and mental health issues.

O’Malley defended the rationale for a more “comprehensive” approach in his remarks Monday.

“It will ban military assault weapons that have no place on the streets of Baltimore or in any other neighborhood in our state, and it will also limit the size of magazines in order to make it harder for criminals to gun down in succession police officers or school children,” he said.

Bloomberg also suggested that critics of gun control are misguided in their argument that such measures infringe upon the 2nd Amendment.

“This is not a constitutional question,” Bloomberg said. “It’s a question of political courage.”

Bloomberg outlined measures he and a large group of mayors would like to see President Obama and Congress take to address gun violence.

Among them: requiring background checks for all gun sales, including private sales that are not covered by current law; making gun trafficking a federal crime; and a federal ban on “military-style weapons” and magazines that accommodate more than 10 bullets.