At least a dozen people became sick in San Diego Sunday after they apparently ingested a batch of synthetic marijuana, also known as "spice", police said.

San Diego Fire Rescue Capt. Joe Amador told Fox 5 that the victims were mainly young people, including a 13-year-old. Amador said it was not immediately clear whether the victims took the drug voluntarily.

The station reported that the victims experienced symptoms varying from a bloody nose to seizures. Medical officers responded to multiple calls reporting sick patients in at least three locations in downtown San Diego.

"They are disoriented, they are slightly hallucinogenic," San Diego Police battalion chief Mike Finnerty told NBC San Diego. "They ramble when they talk."

San Diego police said the drug was being sold in black packages with blue dragons on the side. A police spokesman told the San Diego Union-Tribune that officers were trying to track down victims and witnesses, and were also warning the public about the overdoses in case others had purchased the drug in the downtown area.

"[The drug is] a manufactured substance and depending on who manufactured it it could be of different qualities, different strengths," Finnerty said. "It could be that the current batch that these people are accessing is much stronger than what they are used to or it could have some other unknown chemical in it that's not normally in it."

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