A memorial plaque in Sheridan Circle remembers Orlando Letelier and Ronni Karpen Moffitt. (Oliver Contreras/For The Washington Post)

Missing from the May 18 news article “Turkish guards’ violence denounced,” about Turkish security guards’ attacks on D.C. protesters, was any mention of the significance of the location: Sheridan Circle. On Sept. 21, 1976, thugs hired by another government known for human rights atrocities, this one led by Chilean dictator Augusto Pinochet, carried out a deadly car bombing on this exact spot. The victims, Chilean Pinochet critic Orlando Letelier and American Ronni Karpen Moffitt, were colleagues at the Institute for Policy Studies.

For more than 40 years, the IPS has held an annual memorial program in Sheridan Circle to call for justice for Letelier and Moffitt and other human rights victims. The family members, human rights activists and government officials who have gathered there have transformed this traffic circle from a place of violence into a symbol of peace and justice. Last year, Chilean President Michelle Bachelet, a torture victim, spoke at this event. And over these many years, while Pinochet himself never stood trial, there have been measures of justice, including the imprisonment of other high-level military officials.

The thugs who carried out the attacks Tuesday desecrated this hallowed ground. They must be held accountable.

Sarah Anderson, Washington

The writer is director of the Global Economy Project at the Institute for Policy Studies.