The Indonesian navy seized a Chinese fishing boat after the vessel did not heed warnings to stop fishing in an Indonesian region of the South China Sea, the Associated Press reported Tuesday. The incident is just the latest controversy in the area as relations between neighboring nations have become increasingly strained.

The incident took place Monday when a frigate intercepted the fishing boat near the Natuna Islands, which are part of the exclusive sovereign land of Indonesia, as China acknowledged in November. After multiple warnings, the frigate fired shots into the stern of the fishing boat and captured the vessel and its crew, according to an Indonesian naval command spokesman. No one was hurt in the process.

"This arrest was made to show the world that Indonesia will take firm action against ships that violate our territory," said navy western fleet command spokesman Major Budi Amin, the AP reported.

Tensions have been rising throughout the region as China has looked to bolster its large land claims by building clandestine islands. The U.S. has joined in the controversy by sailing its ships through areas Beijing claims as its own sovereign territory, while the U.S. insists they are international waters. China announced last week that it would send submarines armed with nuclear missiles to the region in response to U.S. involvement in the dispute.

Several nations in the area, including Indonesia, the Philippines, Vietnam, Malaysia, Taiwan and Brunei, have submitted land claims over some portion of the South China Sea. China has by far submitted the largest claim and asserts that most of the region is its sovereign territory.

While China recognizes that the Natuna Islands are Indonesia’s territory, Beijing often cites the nine-dash line drawn after World War II as justification for Chinese fishing boats frequently working in the water near those islands. The nine-dash line is the demarcation used by China to draw its claims in the South China Sea.