SEOUL, South Korea — North Korea fired three short-range guided missiles into its eastern waters on Saturday, a South Korean official said.

The North fired two missiles Saturday morning and another in the afternoon, South Korean Defense Ministry spokesman Kim Min-seok said. He said the North’s intent was unclear.

His ministry said it is watching North Korea carefully in case it conducts a provocation against South Korea.

In March, North Korea launched what appeared to be two KN-02 missiles off its east coast. Experts believe the country is trying to improve the range and accuracy of its arsenal.

North Korea is banned from testing ballistic missiles under U.N. Security Council resolutions.

Earlier this year, North Korea threatened nuclear strikes on Seoul and Washington because of annual U.S.-South Korean military drills and U.N. sanctions imposed over its third nuclear test in February. The drills ended late last month.

This past month, the U.S. and South Korea ended another round of naval drills involving a nuclear-powered aircraft carrier off the east coast. North Korea calls such drills preparation to invade the North.