ABOARD ZHENGZHOU, May 22  -- Chinese and Russian navies on Thursday completed a defense exercise against the intrusion of unidentified boats as part of their ongoing naval drill "Joint Sea-2014".

Upon spotting unidentified cutters and combat divers, China's missile destroyer Zhengzhou sounded the alarm for anchorage defense and the crew used spotlights and verbal warnings to force away the cutters while sending emergency boats to approach the targets for more intelligence.

With 14 Chinese and Russian vessels, the exercise lasted for two hours and concluded with the cutters driven away and the divers seized.

As a basic naval training, anchorage defense is to secure vessels when anchoring in undefended waters, said Yan Zhengming, captain of a destroyer with the Donghai Fleet which was also involved in the exercise.

Navies of the two countries will also train their capabilities in maritime assaults, anti-submarine combats, air defense as well as identification, rescue and escort missions in the following days.