Hong Kong cops in riot gear pulled passengers off buses for searches and broke out water cannons and tear gas to disperse crowds of protestors Saturday, as tensions rose on the 5th anniversary of the city’s pro-democracy “Umbrella” movement.

“It’s a special day for Hong Kong protesters. We will stick together to fight for freedom,” said Sam, 33, dressed in black and wearing a mask. “Most people think Hong Kong was dying after five years, but many people are still fighting for Hong Kong.”

The latest round of protests, which began in June, has outlasted 2014’s 79-day movement, which got its name because the crowds that occupied the streets of the city carried colorful umbrellas.

Among the symbols of the latest demonstrations are “Lennon Walls” filled with anti-government messages. The walls, scattered throughout the city at bus stops, subway stations and on the sides of buildings, are covered with sticky notes placed in patterns or form images, along with images and slogans supporting the pro-democracy movement.

The structures are named after a wall in Prague that was originally filled with messages inspired by musician John Lennon’s lyrics and peace-seeking politics when he was shot in 1980. Similar walls have since popped up in other cities, particularly during political turmoil.

Many of Hong Kong’s walls were torn down last week by pro-China factions. In response, demonstrators on Saturday rebuilt them, and went a step further by plastering slogans and fliers in subway stations and on streets throughout the city.

In some spots, photos of Hong Kong CEO Carrie Lam and Chinese Premier Xi Jinping were affixed to walkways at the top of escalators, so that exiting passengers had to walk over their faces.

While such pranks initially set a lighthearted tone on Sunday, pro-democracy demonstrators found that police were in a more serious mood. Multiple social media posts showed double-decker buses heading into the heart of the city pulled over for passenger searches.

And the evening ended with another violent episode, as police fired tear gas and a water cannon at a massive crowd of demonstrators who gathered downtown Saturday evening outside government buildings. Police said the crackdown was in response to protesters throwing bricks and Molotov cocktails at the buildings and aimed laser beams at a helicopter, posing “a serious threat to the safety of everyone” in the area.

Three months of protests have gridlocked Hong Kong and turned violent multiple times, with protesters smashing the doors of the legislative building and vandalizing subway stations, and setting fires in the streets. Police have used tear gas and pepper spray against demonstrators, along with more violent actions including beating some protester in subway stations.

Students account for 29 percent of the nearly 1,600 people who have been arrested, the Associated Press reported.

With the 70th anniversary of the People’s Republic of China on Tuesday, the pro-democracy movement plans another series of protests, including at the consulate of the former colonial power, Britain, which turned the city over China in 1997. Pro-China demonstrators are expected out in force on Tuesday as well.

The movement started as an objection to an extradition bill that has since been withdrawn, but the movement now has other goals, including the ouster of Beijing-backed Carrie Lam, the chief executive of the city, and a probe into alleged police brutality.

With Post wires