The United States is denouncing North Korea for its firing of artillery into the Yellow Sea on Wednesday.

State Department spokesman Philip Crowley told reporters Wednesday that the North’s declaration of no-sail zones and the firing of artillery shells into areas near the maritime border with South Korea are provocative actions and as such are not helpful.

The North’s firing of artillery is seen by some as Pyongyang’s way of showing its discontent with a lack of peace treaty talks. The U.S. has said that such talks will not take place until the North agrees to return to the six-way denuclearization dialogue.

Crowley added that the U.S. will continue to look into the situation to try to determine the North’s intent behind the firing of artillery.