A search for 10 missing sailors after a cargo ship sank off the Shanghai coast was launched on Sunday.

The Shunqiang 2 collided with another ship, the Yong'an, outside the Wusongkou port near No 64 light buoy at 1:38 am on Sunday, according to the city's maritime search and rescue center.

Shunqiang 2 sank and at least some of its 13 sailors went overboard.

After receiving a distress call, the center sent 17 boats to the scene and alerted nearby passing ships.

One rescue helicopter scouted the area from 5:23 am to 8:20 am and from 10:26 am to 12:56 pm. Rescue divers arrived at the site at 9:55 am, and began searching for the missing sailors.

By Sunday night, three people were saved, while the rest remain missing.

The Yong'an was able to stay afloat and the sailors on board were safe, according to the center.

Loaded with 3,000 metric tons of steel, Shunqiang 2 was on its way from Nanjing, Jiangsu province, to Guangzhou, Guangdong province.