As the People's Liberation Army upgrades its navy, commissioning dozens of new ships under a watchful global eye, a less noticed force, China's maritime militia, is also improving its operational capability.

Despite a history that can be traced back to as early as the 1970s, China's maritime militia remains weaker compared with the land militia due to a lack of government funding and volunteers.

However, the situation has changed as a result of the country's efforts to strengthen its maritime capabilities and safeguard its interests at sea.

According to the PLA Beihai City Military Command in the Guangxi Zhuang autonomous region, the proportion of maritime militia in the city increased tenfold over the past two years, from less than 2 percent at the end of 2013 to more than 20 percent last year.

That enabled the city's maritime militia to play a bigger role in drills organized by the PLA Navy - in 2013 it participated in only one such exercise, while it took part in four naval drills in 2014 and seven drills last year.

Most of the maritime militia is made up of local fishermen.

Senior Colonel Xu Qingduan, commander of the PLA Beihai City Military Command, said the city's maritime militia has been required to take part in more air and naval exercises since 2014 while the land militia's role has shrunk.

This fact pushed the command to negotiate with city government departments on the expansion of maritime militia, he said, adding that the government and the military decided to give more favorable policies and financial support to the civilian sea force.

A number of Navy veterans and experienced sailors have been recruited in Beihai's maritime militia and 10 specialized teams have been established for transport, reconnaissance, obstacle clearance, medical service and equipment repair.

The maritime militia recently worked with Navy warships in a joint operation drill and successfully fulfilled their designated tasks, according to Xu's command.

Beihai is not alone in improving its irregular maritime force.

Hainan's Sansha, China's youngest city that administers vast island groups and their surrounding waters in the South China Sea, is enhancing its maritime militia's training and giving more duties to the force.

Local fishermen have assisted more than 250 law enforcement operations at sea over the past three years.

Jiangmen in Guangdong province is also organizing realistic sea operation exercises for local militiamen to strengthen their combat capability.

Statistics released by China's fishery authorities showed the nation had nearly 21 million fishermen in 2013, the most in the world.

According to the latest information published by the Food and Agriculture Organization of the United Nations in 2012, China had nearly 439,000 motorized fishing vessels that could operate at sea.