North Korea fired two rounds of missiles Thursday, its second launch in a week, South Korea said.

The missiles were fired east “from Sinori area located in Northern Pyongan Province” about 4:29 p.m. and 4:49 p.m. local time Thursday (around 3:30 a.m. ET), the South Korean Defense Ministry said.

The launch came just days after North Korea on Saturday fired what were described as several short-range projectiles. A South Korean military official has said that the launch was thought to involve multiple rocket launchers, including "new tactical guidance weapons."

After Pyongyang's firing of missiles on Thursday, the president of South Korea said he believes his country's northern neighbor is unhappy that a summit with President Donald Trump in Hanoi, Vietnam, fell apart earlier this year.

"It is difficult to know the accurate purpose of their actions, but after analysis, we believe that North Korea is discontented about the outcome of the Hanoi summit," South Korea President Moon Jae-in said in an interview with South Korean broadcaster KBS.

"If they have any discontent, North Korea should talk about it," Moon said. "By acting like this, misinterpretations can accumulate, and this could aggravate the dialogue or negotiation mood, and we would like to let them know about this message."

North Korean state media KCNA said North Korean leader Kim Jong Un observed that launch. KCNA claimed the launch was a drill "to estimate and inspect the operating ability and the accuracy of striking duty performance of large-caliber long-range multiple rocket launchers and tactical guided weapons."

Experts who analyzed photos from the North Korean state media say it's clear the county tested a new solid-fuel missile that appears to be modeled after Russia's Iskander short-range ballistic missile system, The Associated Press reported Wednesday.

A spokesman for North Korea’s foreign ministry was quoted by KCNA as saying on Wednesday that last week’s launch was a self-defensive military drill, and the official criticized it being branded as provocative.

But many viewed it as a sign of Pyongyang's growing frustration over stalled diplomatic talks with Washington over its nuclear arsenal.

People watch a television news programme showing file footage of North Korea's projectile weapons, at a railway station in Seoul on May 9, 2019. Jung Yeon-Je / AFP - Getty Images

Trump and Kim abruptly ended their summit in Hanoi in February after they were unable to negotiate a denuclearization deal.

At the time, Trump indicated the talks fell apart over Kim's demand that all sanctions be lifted in exchange for concessions on Pyongyang's nuclear weapons program. The U.S. has indicated that the sanctions will stay in place until North Korea makes more significant moves.

There have since been no publicly known high-level contacts between the U.S. and North Korea, although both sides say they are still open to a third summit.

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After Saturday's launch, Trump tweeted his optimism that a "deal" would still happen.

"Anything in this very interesting world is possible, but I believe that Kim Jong Un fully realizes the great economic potential of North Korea, & will do nothing to interfere or end it," Trump said in the May 4 tweet.

North Korea has conducted six suspected nuclear tests, most recently in September 2017.

In November 2017, North Korea launched a missile that Western officials said appeared to be an intercontinental ballistic missile.

In April 2018, Kim announced the country had suspended further nuclear tests, claiming they were unnecessary.