Some 500 people were detained Tuesday for violating an overnight curfew in Tbilisi, the Georgian capital, as the official death toll from weekend rioting rose to 18.

More than 140 people were reportedly still hospitalized.Official flags were hanging at half-staff in the city and people were dressed in black as an official day of mourning got under way, local journalists told Reuters by telephone.

Soviet Foreign Minister Eduard Shevardnadze, sent to his home republic to help restore order, was due to hold a meeting with local intellectuals Tuesday, a Georgian Foreign Ministry spokesman said.

"Black flags are everywhere. But although there are a few minor meetings on the edge of the city, the situation is calm," Jan Gorelyov, a journalist at the Georgian news agency Gruzinform told Reuters.

"Military authorities said around 500 people were detained for violating the curfew, but there were no clashes," he added.

Tanks and armored cars were still on the streets, but public transport and most shops and businesses appeared to be working normally again, he said.

Georgian television, quoting the Ministry of Health, announced that two more people died in intensive care, taking the death toll to 18.