Gray skies added to the somber mood Thursday at the town's annual ceremony marking the 13th anniversary of Sept. 11, 2001, terrorist attacks as police, firefighters, residents and town employees gathered in front of Fire Department headquarters.

A large American flag was draped from the Reef Road fire station, and another hung from Police Department headquarters across the street.

"After 13 years, what do you say?" said Police Chief Gary MacNamara. "I don't know what to say anymore, other than to say, `thank you for being here.' "

MacNamara said the terrorist attacks -- at the World Trade Center in New York City, the Pentagon in Washington, D.C., and a plane that crashed into a Pennsylvania field -- are the kind of event that will never be forgotten. "This one is such a collective memory," MacNamara said. "We all have this deep memory of what occurred."

The nearly 3,000 people killed that day included 343 firefighters, 34 police officers and 20 EMTs died that day, Fire Chief Richard Felner said.

"They were not killed in the line of duty, they were murdered," Felner said. "While we didn't know all the firefighters and police officers personally, we knew them because they are us."

State Sen. John McKinney, R-Fairfield, noted that Thursday's ceremony would be his last appearance at the observance as an elected official, though he promised he will continue to attend and watch from the sidelines.

He said he regrets he was unable to do more for first responders during his time serving in the General Assembly. "If you go into a burning building and break your leg, the system will protect you," McKinney said. "But if you see one of you die in that building, the system is not going to protect you. I'm disappointed I wasn't able to do more to fix that."

Probate Judge Daniel Caruso noted that Thursday's ceremony came a day after President Barack Obama had announced a national strategy to deal with the fundamentalist threat posed by ISIL. "We know the struggle will continue" to ensure American liberty and the chance for others in the world to experience that liberty, "but so will we," Caruso said.

"We all know where we were that day," First Selectman Michael Tetreau said, a day that "our lives have changed forever."