(CNN) -- The death toll rose to seven Thursday from a bombing outside a planned performance by a dance company in Russia, officials said.
About forty people were injured in the Wednesday bombing. The bomb went off outside a community center in the southwestern Russian city of Stavropol, according to the Investigation Committee of the Russian Prosecutor's Office, which called the explosion "an act of terror."
The blast happened about 6.45 p.m. (10:45 a.m. ET), 15 minutes before the Chechen dance company Vainakh was scheduled to perform, the committee said.
One of the dead included a pre-teen girl, according to state-run news agency RIA-Novosti.
Early reports indicate the bomb was detonated by remote control and used about 200 grams (7 ounces) of explosives, said Yekaterina Danilova, a spokeswoman for the committee. The device was packed with small metal objects meant to inflict maximum harm, she said.
Stavropol is about 625 miles (1,000 km) south of Moscow.
There was no immediate claim of responsibility. But Islamist groups from the North Caucasus have been behind a string of recent attacks, including April bombings in the republic of Dagestan and March bombings at Moscow subway stations that killed nearly 40 people and wounded dozens. A Chechen rebel leader, Dokku Umarov, claimed responsibility for the subway attack.