HK police fire water cannons with blue water and tear gas to dispel protesters illegally assembled in Mong Kok on Sunday. Photo: Wang Cong/GT

Thousands of protesters took to Hong Kong's streets on Sunday defying a police ban on the assembly and once again turning the city into a theater for violence. 

During a rainless afternoon, protesters formed a phalanx of umbrellas in the narrow streets of Kowloon area. Some wore masks, despite a government ban. They asked journalists not to take their pictures, apparently showing their awareness of the law.

Nearby stores were again closed for business, and security guards appeared to be on high alert outside shopping malls.

Some protesters waved the Catalonia flag, echoing the pro-independence protests in Spain, where protesters clashed with police and Barcelona's Mayor Ada Colau pleaded for calm.

On Sunday, water-filled barriers were placed outside West Kowloon station, where few people were spotted as police used loud speakers to ask passers-by to leave the area.

China Railway suspended operations of several trains between the mainland and Hong Kong on Sunday. Online posts had indicated that rioters were planning to attack mainland people at the West Kowloon station.

Hong Kong police said on Sunday night that they detonated a suspected bomb found at the intersection of Tong Mi Road and Lai Chi Kok Road on Sunday afternoon. The suspect object was a paper box with visible electric wires. The police investigation is ongoing.

As unrest in Hong Kong entered the 20th week, rioters continued to target companies with mainland connections. On Sunday, they smashed and vandalized branches of several Chinese mainland banks including Bank of China and China Merchants Bank. They also "mistakenly" vandalized a branch of the Hong Kong-based Bank of East Asia near the Mong Kok MTR station. 

In Mong Kok, black-clad rioters set up barricades and hurled bricks and bottles at the police. Many public facilities including traffic lights and guard rails were destroyed.

The Hong Kong police dispersed illegal protesters more quickly by deploying water cannons that sprayed blue water and firing tear gas. 

Soon-to-be released murder suspect Chan Tong-kai, whose alleged murder of his girlfriend was the reason Chief Executive of Hong Kong Special Administrative Region (HKSAR) Carrie Lam  introduced an extradition bill which turned out to be the fuse of the current chaos in the city, wrote to the city's leader saying he will voluntarily turn himself over to Taiwan police. 

The HKSAR government said on Sunday that the decision of Chan to surrender himself to Taiwan authorities is purely out of his own free will. The allegations that Chan was manipulated to surrender or his decision was out of political maneuvering are totally groundless, a statement by the HKSAR government said. 

Chan is due to be released from prison on Wednesday after being convicted a year ago of minor charges including money laundering. 

Chan could never have imagined that his case would spark months-long protests in Hong Kong, Witman Hung Wai-man, principal liaison officer for Hong Kong at the Shenzhen Qianhai Authority, told the Global Times on Sunday.   

Taiwan media reports said Taiwan authorities will not allow Chan, and the pastor who persuaded him to surrender, to enter Taiwan.

Hung said Chan's surrender will not ease the situation in Hong Kong and the refusal by Taiwan leader Tsai Ing-wen and her authorities not to allow Chan to enter Taiwan shows their hypocrisy and evil intentions.