The Ukrainian tug, Naftogaz-67, sank after colliding with a Chinese vessel off the southern coast of China, near Hong Kong. Out of the 25 sailors on board, only seven were rescued.
The South China Morning Post also said the Naftogaz-67 tugboat had been detained three times in ports around the world in the past five years over various violations.
The tugboat was last checked in south China last October, when inspectors detected six safety violations, including navigational. Leaking oil, as well as power and support system failures were also noted.
Earlier this week, Anatoliy Prisyazhnyuk, the owner of the Ukrainian vessel, blamed the Chinese dry cargo ship for the fatal collision. The Chinese vessel suffered minor bow damage and remained afloat.
A Ukrainian delegation of officials from the emergencies, transport and fuel and energy ministries arrived in Hong Kong late on Tuesday to look into the cause of the accident.
China will dispatch Asia's largest floating crane to the area by Friday. The crane was used late last year to raise the 800-year-old Nanhai 1 merchant ship.
