Hundreds of students took part in a surprise march from Admiralty to Central yesterday without seeking approval from the police – one of the first acts of civil disobedience since Occupy Central leaders declared an “era of disobedience” on August 31. And they threatened to block roads leading to Government House tonight, when their deadline for talks with Chief Executive Leung Chun-ying expires. The students – who are staging protests all week against Beijing’s decision to rule out an open chief executive election in 2017 – issued Leung with a 48-hour deadline on Tuesday morning, although they were kept at bay by security staff when they tried to approach him. They have called on Beijing to reverse that decision and allow an open nomination process for candidates in 2017. Watch: What do spectators think about striking students' march? Last night, after a third day of activities including public lectures that have drawn about 2,000 people to Tamar Park in Admiralty, near the government’s headquarters, student leaders were finalising their plans. “If Leung does not meet us [by Wednesday night], it’s unlikely he will do so on Thursday,” said Alex Chow Yong-kang, secretary general of the Federation of Students, the organiser of the boycott. “So we need to step up our action to press the government, and to tell society that the boycott isn’t just about attending lectures [at Tamar Park].” Chow said they would block roads leading to Government House after tonight’s gathering if Leung continued to ignore their demand for talks. The week-long boycott could also be extended. Cardinal Joseph Zen Ze-kiun, who was among the speakers yesterday, said: “Democracy is about participation. That Beijing disallowed public nomination has shown it does not trust the people.” Executive councillor Fanny Law Fan Chiu-fun said a meeting between students and Leung at this stage might not be constructive. She urged students to calm down after the boycotts and the Occupy rally expected on Wednesday. The decision to stage the march without applying for a “letter of no objection” from the police was unexpected. Chow said the federation would inform police of today’s action but would not apply for the letter. Public meetings of more than 50 people and marches with more than 30 participants require a “letter of no objection” from the police by law. Police warned yesterday that the march was unauthorised. Organisers said around 700 students and members of the public took part in the march, and some 5,000 attended the Tamar Park gathering last night. The march appeared to be peaceful and to cause minimal disruption. Police warned that participants could be prosecuted in future. At the march, 19-year-old Form Six pupil, Lau Tzar, who was in his school uniform, said: “My school didn’t encourage us to boycott classes but the headmaster said the punishment will be light … My parents also respected my decision.” He said he had an exam coming up, so apart from listening to lectures at Tamar Park, he spent time preparing for his exam. “I think the lectures are even better than my classes at school … [The lectures] are very in-depth, such as explaining about the link between land ownership and democracy. “Democracy means allowing the people to speak their mind, but what [Beijing] gives us is just fake universal suffrage.” Meanwhile, the federation’s application to use Tamar Park for a gathering on Friday was rejected by the Leisure and Cultural Services Department. It will apply to use Tim Mei Avenue outside the Legislative Council instead. Occupy co-founder Benny Tai Yiu-ting said last night that Hongkongers would now need to sacrifice more for democracy, and he again hinted that its mass sit-in in Central could take place next Wednesday. “What the older generations sacrificed was time and effort. Now, we may need to sacrifice our freedom … If you are willing to sacrifice, let’s meet in Central next week,” Tai said.