Is the Public Security Bureau afraid of the Bureau of Letters and Calls?

Not afraid. According to the personal database, the Public Security Bureau and the Bureau for Letters and Calls are administrative units at the same level. The Bureau for Letters and Calls is the petition work organization of the people's governments at or above the county level, and is the administrative organization responsible for the petition work of the people's governments at the same level. People's governments at all levels and departments of people's governments at or above the county level shall do a good job in letters and visits, seriously handle letters and visits, and listen to the opinions of the people.