About six hours after the body was found, police caught Zhou and his wife in Fengxian district.
Wang, the press officer, stressed that police were still investigating the case and could not confirm whether Zhou was telling the whole truth about the incident.
"Along with the suspect's confession, police can find out what really happened from an autopsy of the victim's body and testimony from witnesses, if there are any," said Zhang Peihong, a criminal lawyer from the Huiye Law Firm.
Finding a murder's true motive can be complicated, Zhang told the Global Times.
The police will probably also check whether Zhou had any emotional or debt problems related to the case.
He added that the suspect will likely be charged with intentional homicide.
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