WASHINGTON / BEIJING — U.S. military statistics indicate that American naval forces have had more than a dozen unsafe encounters with Chinese forces over the last two years.<br /><br />Commander Nate Christensen, spokesman of the U.S. Pacific fleet, told CNN there have been 18 unsafe or unprofessional interactions with China and one with Russia since 2016.<br /><br />Most incidents reportedly happened during 2017. At least three that took place in February, May, and July involved Chinese fighter jets unsafely intercepting Navy surveillance planes.<br /><br />The U.S. frequently conducts freedom of navigation operations in the South China Sea to challenge China's maritime claims in the area. This has resulted in several incidents throughout the years.<br /><br />The most recent encounter occurred on September 30 while the USS Decatur was sailing near Gavin Reef in the South China Sea's Spratly Islands.<br /><br />PRC destroyer Luyang reportedly came within 135 feet of the American vessel's bow, forcing it to maneuver to avoid a collision.<br /><br />The U.S. Air Force has had at least one encounter with China during the same period. In May 2017, Chinese SU-30 fighter jets came within 150 feet of a radiation detection plane over the East China Sea. One SU-30 was reportedly flying upside down directly above the American plane.<br /><br />Incidents are typically addressed through diplomatic and military channels, but the frequency of such encounters raises the possibility of a collision or clash that could spark major conflict between Washington and Beijing.<br /><br />Sino-U.S. tensions have been high in recent months, with the two countries embroiled in a bitter trade dispute. The Trump administration also previously sanctioned China for buying Russian fighter jets and missiles.