Rescuers spray foam to extinguish flames on the stricken oil tanker SANCHI off the coast of east China's Shanghai, Jan. 12, 2018. Shanghai Maritime Safety Administration said there is still a large fire on the Panama-registered oil tanker SANCHI. It is likely to explode and sink, the administration said at a press conference on Friday. (Xinhua)

SHANGHAI, Jan. 15 (Xinhua) -- The oil spill on the water surface around the sunken Iranian tanker in the East China Sea is expanding, China's maritime authority said Monday.

The State Oceanic Administration (SOA) said in a statement that several oil slicks were found near the site where the vessel sank and they were much bigger than the previous day.

A 14.8-km-long oil slick was found 7.2 km southwest of the site on Monday morning and another 18.2-km-long slick east of the site at noon, the statement said.

Surveillance planes also reported a slick spreading northward from the site, with a radius of about five km.

The oil tanker which caught fire after it collided with a freighter in the East China Sea a week ago sank Sunday afternoon.

No burning was seen on sea surface from a marine surveillance plane at about 1 p.m. Monday and the oil spill could be easily seen from the air.

The oil spill is likely to move northward due to wind and sea current, the SOA said.

The tanker Sanchi, carrying 136,000 tonnes of light crude oil from Iran, collided with the CF Crystal, a Hong Kong-registered bulk freighter, about 300 km east of the Yangtze River estuary on Jan. 6.