A bomb shook a conference center near Tajikistan's presidential palace yesterday, killing a security guard and scattering debris, just as an EU-run conference was scheduled to start.
The blast, described as a terrorist act by the prosecutor general, occurred at the center only 350m from Tajik President Emomali Rakhmon's palace.
It coincided with the 15th anniversary of Rakhmon becoming head of the former Soviet state, although it was unclear if there was a connection. The site also lies close to a major hotel and the Uzbek embassy.
Police said the dead man was a guard who picked up the device concealed in a plastic bag while inspecting the site.
The conference, which was organized by the EU, was to be devoted to disaster preparedness.
The EU's ambassador in the region, Adriaan van der Meer, said there was no reason to believe the blast was aimed at the EU.
"There is no indication whatsoever that it was against the EU.... We are waiting for exact news, and expect a thorough investigation," he said.
Several hundred people were believed to already be in the building as the blast struck ahead of the opening.
The blast blew out the windows of the building. The dead man's body could be seen lying on the ground covered under a white sheet.
Investigators were combing the scene for evidence.
"At first I thought it was an earthquake," one of those present at the venue said.
Prosecutor General Kurbonali Mukhabbatov said the blast was being treated as terrorism and an investigation was under way.
"We consider this an act of terrorism ... A criminal case for terrorism will be opened. Who carried this out and why will be investigated," he told reporters.
Yesterday's conference was to be attended by Tajik Prime Minister Akil Akilov.
Officials said the opening would be delayed.
The mountainous republic lies on the northern border of Afghanistan and also borders China, Kyrgyzstan and Uzbekistan.
The country was torn apart by a civil war in the 1990s that pitted secular and Islamist factions against each other.
Since a 1997 peace accord Rakhmon has pursued an authoritarian secular course, keeping a tight control on Islamic activism and winning praise from the West.
However, domestic critics accuse him of increasingly interfering in family and religious life, including bans on expensive weddings.