Chinese and Filipino hackers "exchanged fire" in cyberspace over the weekend, adding to the two countries' recent tensions over disputes in the South China Sea.

GMA News Online reported that Filipino "hacktivists" struck back on Saturday at Chinese websites after hackers - "apparently from China" - defaced the official website of the University of the Philippines on Friday.

The news organization reported that the attack targeted some Chinese sites with calls for sovereignty over the Huangyan and Nansha Islands.