In the eyes of activists, Chinese officials are making the public feel like they “are in North Korea.”

Government officials are so concerned about Hong Kong protesters lashing out at a top Beijing official during his visit to the semiautonomous city Tuesday that they've ordered crews to glue down sidewalk tiles -- so activists can't use them as weapons, The China Post reports.

Thousands of police officers were deployed as Zhang Dejiang, China's third-highest-ranking Communist Party official, began his three-day "inspection visit" to the former British colony, where tensions have risen over Chinese rule. Zhang, chairman of the National People's Congress, China's ceremonial parliament, is the most senior Chinese official to visit Hong Kong since then-President Hu Jintao came in 2012.

The security measures also included barricades and officers keeping watch on a mountain peak far from the city center. However, they failed to prevent activists from unfurling a pro-democracy banner lower down the mountainside.

"Keeping protesters away is... ridiculous. It makes you feel like you are in North Korea," Sham Tsz-kit of Civil Human Rights Front, which organizes Hong Kong's annual July 1 political rally, told The China Post.

"Zhang Dejiang is coming here to understand the situation in Hong Kong but now his eyesight will be completely blocked."

After arriving at the airport, Zhang, who's also the Chinese official in charge of Hong Kong affairs, touched on the city's fraying ties with the mainland, saying he would listen to "suggestions and requests from various sectors of society on... the development of the country and Hong Kong."

Zhang is scheduled to deliver a speech at a business conference Wednesday morning. He's also expected to hold a rare meeting with four pro-democracy lawmakers, who said they would urge him to get rid of the city's unpopular Beijing-backed leader, Leung Chun-ying, and revive political reform efforts.

Discontent over Beijing's tightening grip on Hong Kong has risen since pro-democracy street protests rocked the Asian financial hub in late 2014, and calls for independence from radical political groups have become commonplace.

Sidewalk tiles previously were thrown during a February riot involving a pro-independence group that left 90 people injured.

In the neighboring mainland city of Shenzhen, police arrested a Hong Kong man involved in a plot to use a drone to disrupt Zhang's visit, China's official Xinhua news agency reported Sunday.

Police have termed the security moves as "counter-terrorism measures” as "activists have become more violent,” The China Post reported.

The Associated Press contributed to this report.