The skies above Hawaii and Guam are suddenly a busy place for the U.S. Air Force, with fighters here for the regularly held “Sentry Aloha” exercise, and an unprecedented bomber presence on Guam.

Both are certain to get the attention of North Korea and China as tensions rise with those countries.

Sentry Aloha, now underway and running through the end of the month, is hosted by the Hawaii Air National Guard’s 154th Wing and involves multiple types of aircraft including F-22 Raptors from Hawaii as well as F-16s from Texas and Ohio, and F-15s from Japan and Oregon.

The first Sentry Aloha this year involves more than 40 aircraft from eight states and territories and more than 800 personnel, the Hawaii Guard said.

“Sentry Aloha provides tailored, cost-effective and realistic combat training for U.S. Air Force, Air National Guard and other Department of Defense services to provide U.S. war fighters with the skill sets necessary to perform their homeland defense and overseas combat missions,” the Air Guard said in a news release.

The Air Force said history was made this week, meanwhile, when all three of its strategic bombers — the B-52 Stratofortress, the B-1B Lancer and B-2 Spirit — simultaneously took to the sky over Guam in their first integrated bomber operation in the Indo-Asia-Pacific region.

All three aircraft have deployed independently to the Pacific in the past, conducting what the Air Force calls “power projection” sorties.

More than 200 airmen and three B-2 Spirit batwing bombers from Whiteman Air Force Base in Missouri deployed to Guam as part of the “bomber assurance and deterrence” mission, while “several” B-1s are replacing the B-52s under what’s known as the “continuous bomber presence” rotating missions to Guam that have been ongoing since 2004.

The stealthy B-2s, which arrived “as a demonstration (of) commitment to the region,” will conduct local sorties and regional training and integration with partner nations, the Air Force said.

The Hawaii Air Guard held Sentry Aloha exercises in January and March 2015, with the March iteration including 45 aircraft and over 1,000 personnel.

The current exercise marks the first Sentry Aloha this year because the Hawaii Air Guard was busy with a Middle East deployment in which F-22s participated in strikes against the Islamic State group in Syria and Iraq. The fighters returned to Hawaii in April.