China is investigating a Canadian couple who ran a coffee shop on the Chinese border with North Korea for the suspected theft of military and intelligence information and for threatening national security, China's Foreign Ministry said Tuesday.

The official Xinhua News Agency identified the two as Kevin Garratt and Julia Dawn Garratt. In a brief report, Xinhua said the State Security Bureau of Dandong city in northeast Liaoning province was investigating the case, adding it involved the stealing of state secrets.

Neither the Foreign Ministry nor Xinhua said if the couple had been detained, although the ministry said the Canadian Embassy in Beijing was notified Monday and that the couple's "various rights have been fully guaranteed."