North Korea appears to be building another missile launch pad on the same site it used to shock the world by launching its first ICBM earlier in the year.
New satellite pictures – taken by Image Sat International – show construction work at the Panghyon Aircraft Factory in North Pyongyang.
The images emerged as the country was celebrating after this week's launch of an intercontinental ballistic missile by North Korea capable of targeting all of the U.S. mainland, potentially with a nuclear warhead.
Crowds celebrated with fireworks and dancing street parties.
North Korean General Pak Young Sik told crowds the country had “successfully realized” a “national nuclear force.”
South Korean officials said on Friday that, as alarming as this week's launch was, the new ICBM isn't fool-proof. South Korean defense official Yeo Suk-Joo said “additional verification” was needed on, among other things, “atmospheric re-entry.”
Nikki Haley, U.S. Ambassador to the UN, warned this week the regime would be “utterly destroyed” if it tried to start a war.
Russian Foreign Minister Sergey Lavrov called Haley’s comment a “blood-thirsty tirade.”
As a precaution, Hawaii tested attack warning sirens on Friday. It will be repeated every month in one of the closest states to North Korea. The exercises have not been done since the Cold War era.
Hawaii Gov. David Ige said it is “imperative” to be prepared for any “disaster,” including a “nuclear attack.”
He said the new test will ensure the public knows what they should do in case of an imminent attack. If a missile is launched, residents and tourists would have less than 20 minutes to take shelter, officials said.
Lorraine Godoy said the tests are a "reminder that this is not a safe world anymore. Even here, in Hawaii, it's not safe."
Tourism officials disagree, saying travelers "should not be alarmed by the testing."
"Its implementation is consistent with the state's longstanding policy to be prepared and informing the public well in advance of any potential threat to Hawaii's well-being," George Szigeti, president and CEO of the Hawaii Tourism Authority, said in a statement.
The Associated Press contributed to this report.