Mayor Michael Bloomberg and Boston Mayor Thomas Menino opened an all-day summit Tuesday for their counterparts aimed at coordinating their efforts on curbing crime committed with illegal guns.

The mayors — from cities including Washington, D.C., Philadelphia, Dallas, Milwaukee and Seattle — gathered at the official mayoral residence, Gracie Mansion, to exchange ideas, consult with experts and develop law enforcement cooperation among their cities.

In their opening remarks, Bloomberg and Menino criticized the federal government for not doing enough to stop the spread of illegal guns.

"If the leadership won't come from Congress or from the White House, it will have to come from us," Bloomberg said.

Menino told the story of meeting recently with a sixth grade class in Boston in which 9 out of 10 pupils said they knew where they could find a gun. The 73 homicides in Boston last year, Menino said, marked the highest number in 10 years. He said many of the guns used in those killings came from other states.

"Gun crime is a national problem that needs a national response," Menino said. "One of the biggest problems is how we as mayors can work together."

Bloomberg has zeroed in on gun control as a priority for his second term. Crime statistics show the number of shootings this year is slightly lower than last year, but high-profile gun deaths — like that of a toddler killed by a stray bullet on Easter Sunday — continue to hold a spotlight on the issue.

Bloomberg recently testified before Congress with harsh words against a bill that would prevent authorities from being able to share gun trace data with local governments. Some municipalities had used the information to launch lawsuits against gun manufacturers and dealers.

Bloomberg has accused the federal government of being "asleep at the wheel" on helping cities deal with illegal guns.

The mayors summit hopes to create a loose coalition that will trade crimefighting information, work together on city and state legislation and form a louder voice in Washington.

Other mayors scheduled to attend were from the cities of Providence, R.I., Hartford, Conn., Trenton, N.J., Jersey City, N.J., and Buffalo, N.Y. The mayor of Rochester, N.Y., had to cancel to attend a funeral.