A rescue ship works to extinguish the fire on the stricken Iranian oil tanker Sanchi in the East China Sea, on January 10, 2018 in this photo provided by Japan’s 10th Regional Coast Guard. Picture taken on January 10, 2018. 10th Regional Coast Guard Headquarters/Handout via REUTERS

BEIJING (Reuters) - The stricken Iranian oil tanker Sanchi keeps exploding, hampering efforts to extinguish the fire and rescue survivors, state media Xinhua said on Friday, citing the Ministry of Transport, as the blaze raged and worries grew the ship may break up and sink.

The week-long rescue effort following the tanker’s collision with a freight ship on Saturday night has been roiled by poor weather, including 3-metre (10 feet) high waves and strong winds, and toxic fumes from the burning oil.

Dozens of the rescue boats were forced to retreat from dousing the tanker with foam on Wednesday due to an explosion.