Exiled Uzbek opposition groups are seeking more international pressure on Uzbek authorities while marking the second anniversary of the violence.
Uzbek groups around the world have staged demonstrations to remember Andijon's victims.
The Uzbek government's version of events at Andijon's Bobur Square differs markedly from stories told by witnesses, human rights activists, and medical workers.
In Brussels on May 12, a group of Uzbek immigrants living in European countries conducted a protest -- labeling Uzbek president Islam Karimov as a "dictator" and urging the European Union to strengthen its sanctions against Uzbekistan.
The European Union is due on May 14 to decide whether or not to keep sanctions in place that were imposed on Uzbekistan after the violence in Andijon.
There were similar demonstrations elsewhere. RFE/RL's Uzbek service correspondent Gafurjon Yuldashev reported on a demonstration in Bishkek, the capital of neighboring Kyrgyzstan.
"Participants of the demonstration held banners in Uzbek, Russian, and English. The banners carried slogans like: 'We didn't forget the tragedy of Andijon,' and 'The Andijon tragedy should not be repeated'."
Human rights activist Bakhrom Hamrayev attended a protest in Moscow.
"It was an authorized protest that took place in front of the Uzbek Embassy," Hamrayev said. "About 15 people participated. Our main demand was to allow an independent international investigation to be conducted into the killings of people two years ago in Andijon."
The Uzbek government has offered a version of the events at Andijon's Bobur Square that differs markedly from the stories told by witnesses, human rights activists, and medical workers.
According to Uzbek President Islam Karimov, the authorities used violence to crush an attempted uprising by armed Islamic militants.
But opposition groups and human rights activists say what happened in Andijon was a massacre of innocent civilians -- and that as many as 1,000 people may have been killed.
Human rights groups also note that the Uzbek government has not allowed an independent inquiry into events there.
(RFE/RL's Uzbek Service contributed to this report)