China deploys missiles on Woody island
Woody Island, a island in the South China Sea occupied by China and claimed by several other countries, is shown in satellite images taken on February 14, 2016 and February 3, 2016, in this handout image provided by ImageSat International N.V. 2016, on February 18, 2016 Reuters

Malaysia said it has detected about 100 Chinese boats encroaching into its waters in South China sea, in the latest incident involving Chinese vessels in the disputed waters.

The flotilla was spotted near Beting Patinggi Ali, also known as Luconia Shoals off Malaysia's Exclusive Economic Zone (EEZ) off Sarawak, authorities said.

Minister in the Prime Minister's Department Datuk Seri Shahidan Kassim said the government has instructed the Malaysian Maritime Enforcement Agency (MMEA) to deploy its assets to monitor the situation.

"Three MMEA vessels have been deployed to the area. The Royal Malaysian Navy (RMN) assets are also there. The Bombardier aircraft has also carried out aerial monitoring in that area and found a group of Chinese fishermen there," the minister said, according to the Bernama news agency.

The minister did not specify what type of Chinese vessels were spotted.

China's foreign ministry spokesman, Hong Lei, said he did not "understand the details" of what Malaysia said about the encroachment.

"Now is the fishing season in the South China Sea ... At this time of year, every year, Chinese trawlers are in the relevant waters carrying out normal fishing activities," Hong said, according to Reuters.

China 'takes over' Philippine-controlled atoll in South China Sea
Map of Spratly Islands detailing occupation by neighboring countries.

The South China Sea dispute came to the fore in recent weeks with China deploying missile batteries and fighter jets to the Paracel island chain and the US holding a summit of Asean leaders in a move to brace up against the Chinese dominance in the region.

Indonesia this week said it would summon Chinese ambassador over a maritime standoff involving Chinese coast guards and Indonesian officials in an area known as the Natuna Sea near the disputed waters of the South China Sea.

China has disputes with countries such as the Philippines, Malaysia, Vietnam and Brunei over maritime borders in the South China Sea.

Earlier this month, the Philippine media said China took over a disputed Philippine atoll in the South China Sea and stationed up to five ships around the fishing ground, local media reported.

Complex web of claims

In 2012, China and the Philippines faced off against each other in a tense maritime stand-off over Panatag (Scarborough) Shoal, which lies 100 km from the cost of Philippines and 500 km away from the cost of China's southern Hainan.

The Chinese then took control of the Shoal and forced the Philippines to release Chinese poachers who had been arrested from the area. The Chinese never left the shoal since then.

China had angered Vietnam and the Philippines in 2012 when it created Sansha city, making it the administrative headquarters for the Paracels.

Again that year, Vietnam alleged China sabotaged its exploration operations, setting off massive anti-China protests in the country.

China lays claim to the whole of the South China Sea , saying the Paracel and Spratly island chains are integral part of the empire from ages.

Taiwan, Malaysia, the Philippines, Vietnam and Brunei also have claims to a clutch of islands, shoals, rocky outcrops, atolls and sandbanks in the sprawling south China sea, making it a theatre of tense maritime dispute.

The US, which has geopolitical interests in the region, has criticised the land reclamation, construction and militarisation activities undertaken by China in these islands.