USS Spruance and USS Preble missile destroyers floated within 12 nautical miles of the Spratly Islands as part of what the US Navy called "freedom of navigation."
The operation was conducted "to challenge the excessive marine claims and preservation of access to waterways, as regulated by international law," Cmdr. Clay Doss, spokesman for the 7th Navy of the United States Navy, told CNN.
"All operations are developed in accordance with international law and demonstrate that the United States will fly, swim and work where international law so permits," added Dos. "This is true in the South China Sea, as elsewhere around the world."
Shortly after this operation, China accused the United States of invading its territorial waters – and said it had launched missiles capable of targeting medium and large
"The US action violated Chinese laws and international laws, violated China's sovereignty, damaged the regional peace , security and order ", said Lu Kang, a representative of the Ministry of Foreign Affairs. "China will take the necessary measures to protect state sovereignty."
During this operation, the Chinese destroyer went to a distance of 45 yards from an American warship, forcing him to maneuver to avoid a collision. The United States described the actions of the Chinese warship as dangerous and unprofessional, while Beijing said the United States threatened the security and sovereignty of China.
The United States accused Beijing of establishing missiles and other military equipment on controversial islands.
"There was a kind of constant growth there," said John Richardson, US Naval Chief, told reporters about the militarization of the area in China.
"Weapons systems are becoming more and more complex, so we are watching very closely," he added.
"We have great interests to stay there," he added, noting that about a third of world trade passed through these waters.
Contribution of Bren Landon CNN of this report.