Talks are continuing between North and South Korea after tensions threatened to boil over into war.

High-level talks continued deep into the night after the first round of talks lasted 10 hours. They began after tensions mounted over alleged propaganda on South Korea’s part that caused North Korea to become aggressive and pushing the two sides, who have technically been at war for decades, to a full-fledged military confrontation, according to an Associated Press report.

As talks continue, South Korea’s military say they see unusual troop and submarine movements in North Korea, indicating that Pyongyang was maneuvering for a potential strike against its rival. An unnamed official said according to the report that 70 percent of the North’s submarines had departed their bases and were no longer detectable. Also, the North has apparently doubled its strength in front-line artillery forces.