The death toll in Wednesday's terrorist attack in Stavropol reached six when a preteen girl died in a hospital, the the southern Russian city's civil defense chief told RIA Novosti.

"A girl died in the regional hospital," Boris Skripka said, adding that she was about 10 years old.

More than 40 people were injured in the blast, which occurred outside the city's House of Culture and Sport early on Wednesday evening before a Chechen band's concert.

Stavropol Territory Governor Valery Gayevsky said the terrorist attack was aimed at shattering national unity.

A top regional investigator, Yekaterina Danilova, told RIA Novosti the explosion was equivalent to 0.2 kg of TNT.

The Stavropol Territory is the largest region in the North Caucasus Federal District, and hosts its administration, but has remained largely free of the violence in the neighboring republics of Chechnya, Ingushetia and Dagestan.

STAVROPOL, May 26 (RIA Novosti)