North Korea began releasing large amounts of water from its Hwanggang dam, located at Imjin River early on Tuesday morning.

South Korea media reported the release was “abruptly” started on Wednesday morning,  raising concern of a North Korean “water attack” (Su-gong) aimed at flooding parts of Seoul, though the claims are inconsistent with government data.

Numerous media outlets, including Yonhap News Agency quoted an anonymous military source and reported that North Korea began releasing water at around 6am on Wednesday. But South Korean government has refused to confirm or deny the report.

“I have read the reports about the water released from ‘Hwanggang dam,’