SEOUL, South Korea (AP) — North Korea is preparing its second attempt to put a spy satellite into orbit as well as tests of long-range missiles to mark a key national anniversary and protest efforts by the United States to strengthen its regional alliances, South Korea’s intelligence service told lawmakers Thursday.

North Korean leader Kim Jong Un has been expected to conduct weapons tests in response to major U.S.-South Korean military drills that begin next week and a trilateral U.S.-South Korea-Japan summit at Camp David in the United States this Friday.

The National Intelligence Service told lawmakers in a closed-door meeting that North Korea may try to launch a spy satellite in late August or early September ahead of the country's 75th anniversary on Sept. 9, according to Yoo Sang-bum, one of the lawmakers who attended the briefing.

The NIS said North Korea has been testing an engine for the rocket to be used for the satellite launch and has installed an additional land antenna to receive satellite data, Yoo said.

Kim has vowed to produce a number of high-tech weapons systems including a military reconnaissance satellite. North Korea attempted a satellite launch in late May, but the rocket crashed into the ocean soon after liftoff. North Korean state media said it lost thrust following the separation of its first and second stages.

South Korea’s military has said that debris from the satellite indicated it wasn’t advanced enough to conduct military reconnaissance as claimed.

The NIS said it also has detected unusually heavy activities at a North Korean facility that produces solid-fueled intercontinental ballistic missiles and at another site related to liquid-fueled ICBMs, Yoo said in a televised briefing.

The NIS said the launch preparations are intended to protest the Camp David summit or the U.S.-South Korean military drills that begin next Monday, Yoo said.

North Korea is extremely sensitive to U.S. efforts to bolster its alliances with South Korea and Japan. Since the start of 2022, it has conducted more than 100 missile tests, saying it needs to strengthen its own military capabilities in response to expanding U.S.-South Korean exercises, which have included a U.S. aircraft carrier, nuclear-capable bombers and nuclear-armed submarines.

North Korea has demonstrated that its ICBMs have the potential range to reach the U.S. mainland, but many analysts believe it still needs to master some remaining technological challenges. Its shorter-range missiles are capable of targeting South Korea and Japan.

Three of North Korea’s four known types of ICBMs use liquid fuels and the fourth employs solid fuel. Solid-fueled missiles are easier to move and fire quickly, making them more difficult to detect before launch.