06/07/2017: This story has been updated to include additional information on the Sunny Oriental.

Several North Korea-linked ships have visited multiple coal ports in China since Sunday, despite a nationwide ban issued by Beijing in February, analysis of satellite imagery and vessel positions shows.

Ships with ties to the DPRK, or sailing under the country’s flag, called in at various coal handling ports in Shanghai and northeast China over the past few days, according to data provided by vessel tracking service Marine Traffic.

NK News observed similar activity in April when several North