WASHINGTON - More than 300 law enforcement officers who died in the line of duty were honored Monday at a naming ceremony in the nation's capital. In an annual tradition, the names of the fallen were added to the National Law Enforcement Memorial Wall, accompanied by a candlelight vigil and musical tributes.

In remarks to an estimated 20,000 officers, families and supporters, Homeland Security Secretary Janet Napolitano said the dead represented "the best of our nation."

"Heroes, patriots and role models who did not flinch at the first sign of danger," she said, "but like all law enforcement, acted to protect us even though their lives were on the line."

The secretary cited the huge multiagency response to Superstorm Sandy, the Texas fertilizer plant explosion and last month's bombing attack at the Boston Marathon as indicative of extraordinary community from the "thin blue line."

"Generation after generation, officers in law enforcement put the uniform on and head out into the world to protect us. They know the risks they face, and tonight we ensure they also know our gratitude and blessings," she said.

Behind her on stage sat Boston Police Department Superintendent Willie Gross, Chief Ed Deveau of Watertown, Mass., and state Police Superintendent Timothy Alven.

Napolitano was followed by Attorney General Eric Holder, whose brother is a retired lawman with the Port Authority of New York and New Jersey. Holder said that although police deaths were at their lowest since the 1950s, the Obama administration would continue to push to close budgetary gaps for police agencies, keep more officers on the street and protect officers.

"It means working with Congress to overcome recent setbacks and to enact common-sense measures to prevent and to reduce gun violence," he said. "To keep deadly weapons out of the hands of those not legally allowed to possess them, and to ensure that every time someone attempts to buy a gun in this country, a full background check is performed."

Holder also said the administration would introduce new measures this year to streamline federal Public Safety Officers Benefits Programs, including management systems allowing families to check the status of their claims online and reducing paperwork required to support a claim.

"The era of red tape in this vital program is over," he said.

Gracing an outdoor park in downtown Washington, the National Law Enforcement Memorial Wall bears the names of more than 19,000 men and women inscribed into it from all 50 states, along with federal and military agencies. In all, 321 new names were added Monday night, including 120 who died in 2012. The remainder where officers whose historical contributions had only recently surfaced.

Craig Floyd of the Law Enforcement Officer Memorial Fund said "whether an officer is killed one year ago or two centuries ago, his memory will be honored here."

House Minority Whip Steny Hoyer, D-Md., FBI Director Robert Mueller and Madeline Neumann of the Concerns of Police Survivors (COPS) were also in attendance. Neumann is herself the widow of a law enforcement officer.

The names of the fallen were read aloud after a candle light vigil with flames numbering in the thousands. But the process for selecting names for recognition isn't always an easy one, as explained by the Associated Press. Of more than 600 considered this year, roughly half were approved.

The dedication falls in the middle of National Police Week in the District of Columbia: seven days aimed at honoring the contributions of law enforcement. Tens of thousands of officers and their supporters from around the country converge on the city annually for a wide range of events from a bagpipe band march to a special charity game by the Washington Nationals baseball team.

This is the 25 th year of festivities. The recognition first started as a proclamation by then-President John F. Kennedy.