Dozens of shoppers in Russia's second city of St. Petersburg were hospitalized due to a mysterious gas that was released in a hardware chain store. Authorities ruled out terrorism, and said the incident probably stems from a business dispute.
A foul-smelling gas sickened dozens of Russian shoppers after it was released into a construction supply store in St. Petersburg.
Two other stores of the supply store chain, Maksidom, were evacuated after workers discovered gas ampoules with what appeared to be timing devices.
The attack came at the height of the busy shopping period leading up to New Year's Day, the main holiday of the season in Russia.
Authorities later ruled out political terrorism as a motive, saying it was almost certainly a business dispute.
One regional security official says the attack was likely carried out by criminals trying to blackmail the stores' managers, who said they had received letters containing threats to disrupt the holiday shopping season.
Business disputes are common in Russia, especially those involving disagreements about property ownership.
However the deliberate targeting of customers is rare.
"It is my understanding that the whole thing was designed to threaten precisely customers," said Vladimir Luzgin, a Russian-American business consultant, who travels frequently to Russia.
Tests are now under way to determine exactly what kind of gas was used, although one official says it appears to be mercaptan, a carbon-hydrogen compound found in high-sulfur oil and gas that is poisonous in high quantities.
Witnesses described the gas as smelling like garlic or rotten cabbage, and said they quickly felt nauseous.
The Internal Affairs Ministry in St. Petersburg has opened a criminal investigation into the case.