A former police chief will take over as number two in Carrie Lam's Hong Kong government as China continued its push for central government control of the former British colony on Friday.

Secretary for Security John Lee takes the place of Matthew Cheung as the city's Chief Secretary, in what Hong Kong leader Lam described as a move "to improve national security."

The changes come after pro-democracy newspaper Apple Daily published its last edition this week and a year since protests against a proposed extradition law which was later canceled.

What are the main changes to the government?

With John Lee moving to take the number-two role in government, the current chief of police, Chris Tang, is now being appointed secretary for security. Tang's deputy in the Hong Kong police force, Raymond Sui, will now become its head.

Matthew Cheung, who has served as secretary of state for the last four years, will leave his post — although he seemed adamant to continue his work, according to the South China Morning Post.

"I will continue to serve the society and contribute to this country," Cheung told journalists who were gathered next to his home.

In his new role as chief secretary, Lee will be in charge of key departments such as education, welfare, health, transport and housing.

The changes were announced by Carrie Lam in a press conference Friday morning after a decision by the Chinese government on Wednesday, according to its state-run Xinhua news agency.

Why are the changes controversial?

The move to change the leadership of the former British colony of Hong Kong followed the publication of the last edition of the pro-democracy newspaper Apple Daily.

Police arrested five editors and executives, accusing them of endangering national security, and froze $2.3 million of the holding company's assets during recent raids.

The moves at the top come after an extradition law, which triggered massive protests across Hong Kong, was overturned last year.

jc/msh (AP, EFE)