YONGJI, Shanxi -- Two labor watchdog officers in Yongji city of north China's Shanxi Province have been detained by local police in connection with the kiln slavery scandal.

Hou Junyuan, head of the labor inspection team of Yongji City's Labor and Social Security Bureau, was accused of dereliction of duty and detained on Thursday afternoon.

Another officer from the team, Shang Guangze, was arrested on charges of abuse of power.

The two had transferred an under-aged laborer, who was from central China's Henan Province and being sent back home, to another kiln for new employment.

Shang has been sacked.

The detail of the cases is still under investigation.

Police have arrested 168 people and are seeking more than 20 other suspects involved in the forced labor scandal.

By Sunday night, about 45,000 policemen had raided more than 8,000 kilns and small coal mines in the two provinces and freed 591 workers, including 51 children.

The criminals are suspected not only of illegal employment practices, but also of abduction, limiting others' freedom, employing underage workers and even murder.