North Korea sent at least two ballistic missiles into Japan’s exclusive economic zone (EEZ) in waters off Ishikawa Prefecture on Thursday, the Defense Ministry in Tokyo said, further ramping up tensions after a failed satellite launch last month.

Both missiles splashed down some 250 kilometers northwest of Ishikawa’s Hegura Island, traveling about 850 km and 900 km, respectively, Parliamentary Vice Minister of Defense Kimi Onoda told reporters, adding that there had not been any reports of damage to aircraft or ships.

Onoda called the launches into Japan’s EEZ, which extends 200 nautical miles (370 km) from its coast, “absolutely unacceptable” and “a serious matter concerning the safety of residents of the country.”