In November 2006, police raided the Chongryon's Tokyo headquarters in an investigation behind an attempt to illegally export 60 bags of intravenous solutions to North Korea. The solution was intercepted by Japanese customs as they were taken aboard "Man Gyong Bong 92". It was reported that the solutions could have been used to make biological weapons, a claim denied by Chongryon. Crowds of Chongryon supporters tried to block access to the building, leading to deployment of riot police. In February 2007, police in Hokkaido raided ten locations linked to Chongryon, including its Hokkaido head office in Sapporo and a famous mutton yakiniku restaurant owned by a senior Chongryon official in Susukino, Sapporo, over alleged tax evasion amounting to tens of millions of yen. Four people, including the restaurant owner and a senior official of Chongryon's Sapporo chamber of commerce and industry, were arrested. Also in February 2007, Police raided several locations including Chongryon's Hyogo headquarters in Kobe, and arrested three people, including Song Gi-hwan, who heads the accounting division of Chongryon's Hyogo chamber of commerce and industry, over alleged unlicensed accounting. Riot police scuffled with a crowd of Chongryon supporters who gathered in protest. Footage of the raids were later released by Chongryon.