Chen, however, was displeased with the situation, despite his deep friendship with Wang, as Wang repeatedly rejected his advice against welcoming Xiao Yuanming. Wang Sengbian's son Wang Yi (王顗) suspected of Chen's intentions and advised Wang Sengbian to watch out for potential attack from Chen, but Wang Sengbian, trusting Chen deeply, did not see Chen as a threat. Chen, indeed, was planning a coup. Meanwhile, news came that Northern Qi was preparing an attack, and Wang Sengbian sent his secretary Jiang Gan (江旰) to Jingkou to alert Chen. Chen, instead, detained Jiang while preparing his forces. He launched a surprise attack on Wang's headquarters at the fortress of Shitou. Wang was caught defenseless, and was forced to surrender. Chen told Wang, "I am surprised that you did not prepare for an attack." Wang's response was, "I entrusted the northern gate to you. How can you say that I did not prepare?" That night, Chen strangled Wang Sengbian and his son Wang Wei (王頠) to death. He subsequently deposed Xiao Yuanming and took over the regency over Xiao Fangzhi, whom he declared emperor (as Emperor Jing), but subsequently seized the throne from Emperor Jing in 557, establishing Chen Dynasty.