“Based on comprehensive research and expert opinion, we decided to temporarily manage the pathogen causing the pneumonia as Class II — highly pathogenic — and imposed biosafety requirements on sample collection, transport, and experimental activities, as well as destroying the samples,” China’s National Health Commission’s Liu Dengfeng told reporters, according to the South China Morning Post.

“If a lab does not have the necessary conditions to store samples, they should destroy the samples on-site or send them to professional storage institutions,” Liu said. “Those are strictly enforced rules.”

Chinese public health laws say that labs that do not meet certain standards must either transfer samples to a qualified depositary for safekeeping or destroy them. China’s National Health Commission reportedly ordered the samples to be destroyed on Jan. 3.