WASHINGTON ( CNN ) -- American fighter jets intercepted two Russian bombers , one of which buzzed a U.S. aircraft carrier in the western Pacific on Saturday , U.S. military officials told CNN Monday . Russia 's Defense Ministry said Tuesday that there was no violation of flight regulations during the incident . A ministry official said the flights are standard operating procedure for air force training . One of them twice flew about 2,000 feet over the deck of the USS Nimitz Saturday while another flew about 50 miles away , officials said . Two others were at least 100 miles away , the military reported . U.S. defense officials said four F/A-18A fighter jets from the Nimitz were in the air . The Russians and the U.S. carrier did not exchange verbal communications . Watch U.S. aircraft carrier USS Nimitz » . Four turboprop Tupolev-95 Bear bombers took off from Ukrainka Air Base , in Russia 's Far East , in the middle of the night , Japanese officials told The Associated Press , adding that one of the planes violated Japanese airspace . Russian bombers have been making flights over the western Pacific for several months . There have been eight incidents off Alaska since July . Among the latest , on September 5 , six F-15s from Elmendorf Air Force Base , adjacent to Anchorage , Alaska , intercepted six Russian bombers about 50 miles from the northwest coast of Alaska . Two similar incidents occurred in August , one near Cape Lisburne , Alaska , and the other near Cold Bay , Alaska , west of the Aleutian Islands . E-mail to a friend .
Japan 's Defense Ministry says there was no violation of flight regulations . One plane twice flew about 2,000 feet over USS Nimitz deck , U.S. military base . U.S. Defense officials say four F / A fighter jets from the Nimitz were in the air . Japanese officials tell AP one of the planes violated their country 's airspace .