HONG KONG (Reuters) - Hong Kong police on Friday withdrew from a university campus trashed by weeks of clashes as pro-democracy activists canvassed social media to promote more protests at the weekend.

Anti-government protesters display messages at a shopping mall during a rally in Hong Kong, China, November 29, 2019. REUTERS/Marko Djurica

Senior members of Hong Kong Polytechnic University toured buildings strewn with debris after police left, including a sports hall and a ruined Starbucks outlet, seeing smashed windows and charred piles of former barricades.

After more than five months of increasingly violent demonstrations, the Chinese-ruled city has enjoyed relative calm since local elections on Sunday delivered an overwhelming victory to pro-democracy candidates.

Activists are trying to keep up momentum, after winning backing from U.S. President Donald Trump that has renewed global attention on the Asian financial hub and infuriated Beijing.

“Many classrooms, laboratories and library were destroyed. Even so, there’s been no loss of life. We insisted on adopting a humane way to solve the crisis,” university president Teng Jin-Guang told reporters, saying the next semester would go ahead on time.

Located on Kowloon peninsula, the campus became a battleground earlier this month when protesters barricaded themselves in and fought riot police in a hail of petrol bombs, water cannon and tear gas.

Police arrested more than 1,300 people during the turmoil at the university, Kwok Ka-chuen, a senior police official, told reporters on Friday. A total of 5,890 people have been arrested since early June, he added.

Before police left, they seized nearly 4,000 Molotov cocktails and hundreds of bottles of chemicals, Kwok said.

At one point on Friday, a man and woman emerged from the campus wearing black face masks and walked out hand-in-hand, with no sign of police.

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“WE ARE ALL SIMON”

Demonstrators are angry at what they see as Chinese meddling in freedoms promised when Britain returned Hong Kong to Chinese rule in 1997. China denies interfering, says it is committed to the “one country, two systems” formula put in place at that time, and has blamed foreign forces for fomenting unrest.

Beijing warned Washington of “firm counter measures” after Trump signed legislation supporting the protesters on Wednesday.

On a visit to Bangkok, Hong Kong Chief Executive Carrie Lam on Friday tried to reassure the Thai government and businesses that her city was still an attractive financial hub.

The anti-government protests have at times forced businesses, government, schools and even the international airport to close. The unrest has hit the economy, with data on Friday showing tourist arrivals fell 44% in October from a year earlier.

A few hundred protesters, some carrying Union Jack flags, gathered at the British consulate on Friday urging London to extend citizenship to Hong Kong residents born before the 1997 handover to China and classified as overseas British nationals.

They chanted “We are all Simon”, referring to a former consulate employee, Simon Cheng, who said Chinese secret police beat him and deprived him of sleep seeking information about activists behind the protests.

Hong Kong’s justice secretary has urged him to report the matter to the relevant Chinese authorities and said she has no opinion on the accusations.

Other demonstrations planned over the weekend include a rally by secondary school students, a protest against the use of tear gas near children, and a “march of gratitude” to the U.S. consulate.

A rally planned for Dec. 8 by Civil Human Rights Front, the group that organised million-strong marches in June, is likely to provide the best gauge of the democracy movement’s support.