The bombers took off from Andersen Air Force Base, Guam, on what the statement called a “routine training mission.”
One bomber conducted training in the vicinity of the South China Sea before returning to base on Guam.
The other aircraft conducted training in the vicinity of Japan alongside Japanese air force counterparts, and in coordination with the U.S. Navy, before returning to Guam as well, the PACAF statement said.
The flights came just three days after U.S. Secretary of State Mike Pompeo, during a visit to Manila in the Philippines, said the United States is committed to ensuring the South China Sea remains open to all kinds of navigation and that “China does not pose a threat” of closing disputed sea lanes.
Pompeo assured the Philippines that America will come to its defense if its forces, aircraft or ships come under armed attack in the South China Sea, the first such public U.S. assurance in recent memory.
The U.S. has declared that the peaceful resolution of disputes and freedom of navigation and overflight in the contested areas are in the U.S. national interest.
In Beijing, Chinese foreign ministry spokesman Lu Kang said China and countries around the South China Sea are committed to maintaining regional peace and stability,
“If countries outside the region, such as the United States, really keep in mind the peace and well-being of the regional people, they should not stir up troubles in the region,” Lu said at a regular briefing.
The sorties were part of the U.S. Air Force’s continuous bomber presence, which the U.S. says maintain the readiness of its forces in the Pacific region.
“The U.S. Indo-Pacific Command’s CBP mission, which have been routinely employed since March 2004, are in accordance with international law and a free and open Indo-Pacific,” the PACAF statement read.
The B-1, B-2 and B-52 have all been rotated through Guam for the continuous bomber presence mission.
Aircraft Spots, an aviation Twitter account that monitors military air traffic, first noted both flights: one from Guam to the South China Sea west of the Philippines, and the other from Guam and eventually into the East China Sea.
The flights over the South China Sea and the East China Sea also serve to reinforce freedom of flight in the region.
China set up an Air Defense Identification Zone over the East China Sea in 2013, which many viewed as an attempt to try and bolster its claims over disputed territories, like the uninhabited Senkaku islands that are disputed with Japan.
U.S. officials have criticized China for setting up the ADIZ, which does not conform with international law and overlaps similar zones operated by Japan, South Korea and Taiwan, without prior consultation.
China has also built man-made islands in the South China Sea and established military facilities on disputed maritime features in an effort to provide credibility to its claims in that region as well.
The Chinese have often called missions by nuclear-capable B-52 bombers over the South China Sea “provocative."
The Associated Press contributed to this report.