Chinese authorities say they are investigating after one of the country’s top police chiefs spent a day at a U.S. consulate, state media said.

“Wang Lijun entered the consulate in Chengdu on Februray 6 and stayed there for a day before leaving,” the official Xinhua News reported, quoting a spokesperson with the foreign ministry.

“The relevant authorities are investigating on the matter,” the agency said.

Wang, known as a crime fighter who has built a national reputation for a crackdown on organized crime, was reportedly to be removed from his post in the juridical system at the turn of the year and is “taking vacation-style therapy”.

“It is understood that Vice-Mayor Wang Li-jun, who has suffered overwork and immense mental stress for a long time, is seriously physically indisposed,” the city government’s news department said on its micro-blog site, “After agreement, he is currently taking vacation-style therapy.”

It is an “isolated incident” and that it had been resolved, said Cui Tiankai, one of China’s vice-foreign ministers Thursday, referring to Wang’s visit to U.S. consulate in Chengdu.