NEW HAVEN, Conn. -- White powder found at the Ikea store in New Haven -- prompting a hazardous materials response -- turned out to be a harmless aspect of a "sport."

Following their investigation, police arrested and charged a New Haven man and his sister.

Emergency crews responded to the store just before 5 p.m. for a white powder found around the entrance and scattered throughout the store. A white powder was also found at a Bank of America branch nearby.

At about 5:45 p.m., hazardous materials crews got dressed in protective gear as they prepared to enter the store. Officials blocked the front of the store and evacuated customers and workers.

Witnesses reported seeing someone spreading something in the area, which prompted the response of city fire, police and health officials, joined by the state police and FBI.

Police arrested a woman shortly after 7 p.m. who officials said matched a witness description. Officials said the woman was with another woman and two men who all claimed to be part of a running club participating in a "strategic sport" called Hash Horse Harriers.

The group told police that they were dropping the substance as part of their game to mark their route.

According to the group members, city officials said, it was tradition before the incidents of Sept. 11, 2001, for their sport to use flour to mark their route during games.

Police detained all four people, one of whom police said admitted to spreading the substance. Police later identified two people charged with first-degree breach of peace in the incident as Daniel Salchow, 35, of New Haven, and his sister, Dorothee Salchow, 31, of Hamburg, Germany.

As a precaution, fire crews plan to sweep through the Ikea store. Store employees told Eyewitness News late Thursday that they were unsure whether the store will reopen on time on Friday.

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