Police in Xiamen, Fujian province, have issued a wanted notice seeking information related to alleged illegal activities by 18 core members of a "psychological warfare brigade" under Taiwan's military affairs department.

According to the notice issued by the public security bureau in Xiamen on Saturday, the group consists of six teams tasked with information-based psychological operations, intelligence gathering and research, tactical psychological operations, radio-based psychological operations, troop morale maintenance and wartime mobilization.

The notice included the identifications, genders and photos of the 18 people involved. Xiamen police are offering a reward of 10,000 yuan ($1,402) for any information that aids their investigations into the group.

The police said their investigations have so far revealed that the suspects have been engaged in various activities such as setting up websites to spread false information and slander, creating seditious games to incite secession, producing fake audio and video content to mislead the public, operating illegal radio stations for propaganda and infiltration, and coordinating external forces to manipulate public opinion.

These actions are aimed at misleading people on both sides of the Taiwan Strait, with the real purpose of promoting the fallacy of "Taiwan independence" and inciting secession, according to the notice.

The public security bureau called on compatriots in Taiwan to recognize the extreme danger and harm of "Taiwan independence" and to take concrete actions to dissociate themselves from separatist forces.

Authorities also encouraged the public to provide relevant information regarding these illegal activities and to join hands with compatriots on the Chinese mainland in opposing "Taiwan independence" separatist activities.

Responding to the "psychological warfare brigade", Chen Binhua, a spokesperson for the Taiwan Affairs Office of the State Council, said on Saturday that any organizations or individuals who act as accomplices to the "Taiwan independence" separatist forces will be severely punished under the law.

"We hope compatriots on both sides of the Taiwan Strait will actively provide information on relevant illegal and criminal activities, firmly oppose all forms of 'Taiwan independence' separatist acts, and resolutely safeguard national reunification, peace and stability across the Strait, as well as their own safety and well-being," Chen said.