North Korea tests 'short-range ballistic missiles'
North Korea has fired two missiles into the sea, its fifth such launch in recent weeks.
The missiles are thought to be short-range ballistic missiles, South Korea's military says.
If the use of such missiles is confirmed it would be a breach of 11 UN Security Council resolutions.
The launches come after US President Donald Trump said he had received a "very beautiful letter" from North Korean leader Kim Jong-un.
Mr Trump said Mr Kim was unhappy with the current US-South Korea joint military exercises.
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What do we know about the latest test?
The missiles were fired from near the eastern city of Hamhung in South Hamgyong Province and landed in the Sea of Japan/East Sea, to the east of the Korean peninsula.
Launched at 05:34 and 05:50 (20:34 and 20:50 GMT Friday), they flew a distance of around 400 km (250 miles), at an altitude of about 48 km with a maximum speed of more than Mach 6.1, a South Korean military statement said.
North Korea has fired a series of missiles and rockets since Mr Trump and Mr Kim agreed during a meeting in June to restart denuclearisation negotiations.
What did Kim write to Trump?
Shortly before the latest launches, the US president spoke of a letter he had received from the North Korean leader.
"It was a very positive letter," Mr Trump told reporters at the White House. "I think we'll have another meeting. He really wrote a beautiful, three-page - I mean great from top to bottom - a really beautiful letter."
The North Korean regime has expressed anger over the US-South Korean military drills, stating that they violate agreements reached with Mr Trump and South Korea's President Moon Jae-in.
Later on Saturday, Mr Trump said Mr Kim had complained "about the ridiculous and expensive" military exercises.
But he said the North Korean leader had offered a "small apology for testing short-range missiles" in recent weeks.
What about the US-South Korean exercises?
While the main drills will start on 11 August, low-key preparation has begun.
The exercises are mainly computer-simulated and are more low key than previous drills between the US and South Korea, which the North has deemed as provocations.
Over recent weeks, the North has test-fired what South Korean officials said appeared to have been a new type of short-range missile, with the previous one coming on Tuesday.
The missiles fired on 25 July - one of which travelled about 690km - were the first since Mr Trump and Mr Kim held an impromptu meeting in June at the demilitarised zone (DMZ), an area that divides the two Koreas.