It was announced on the official website of Hakusensha's Hana to Yume magazine that Akatsuki no Yona will go on an indefinite hiatus due to the Kumamoto earthquakes, which affected areas in the Kyushu region on April 14 and 16.

Mangaka Mizuho Kusanagi, who resides in Kumamoto Prefecture, was unable to complete her manuscripts due to the situations caused by the natural disaster. The editorial department of the magazine confirmed that Kusanagi was not injured from the incident. The mangaka also announced her hiatus on Twitter.

The 123rd manga chapter was supposed to be included in the magazine's 11th issue, to be released on May 2. The series will still be featured on the cover of magazine. More information about the manga's resumption date will be revealed in a future issue, as well as on the magazine's website and Twitter account.

The earthquakes also affected airing anime, as they were replaced by emergency news bulletins regarding the quakes. The series that were affected included Sakamoto desu ga?, Shounen Maid, Koutetsujou no Kabaneri, and more.

Source: Official site

Update May 2
It was revealed via the mangaka's blog that the series will return on the 12th issue, which will release on May 20, 2016.

Source: Mangaka's Blog