Images from the campus show how protesters attack police cars with gas bombs. When the police tried to approach the occupied polytechnic university at 21, local time, a police car was set on fire. The car, which was still in flames, was then forced back to safety before the fire could be extinguished.
"We don't want to attack the police, we just want to protect our area here at the university, and we want to protect Hong Kong," says Chan, a student at the scene.
During confrontations with the police, the protesters have also shot with a bow and used huge homemade snake bells to fire petrol bombs.
A police officer working in the press department was hit in the wad by an arrow during the morning, according to Hong Kong police.
Want to block traffic
During the afternoon, the number of protesters at the Polytechnic University has grown to around a hundred. When police at 18, local time, tried to surround the university protesters, they set fire to an important road tunnel connecting Hong Kong Island with the rest of the city.
The university is at least the fifth in Hong Kong that has been occupied by protesters for periods. Blocking traffic in the tunnel, and thereby disrupting Hong Kong's infrastructure and economy, is one of the protesters' goals.
According to the South China Morning Post, Sunday's clashes began when protesters threw stones at residents of the city trying to clear away pebbles near the university and the tunnel.
Surrealistic mood
Stockholm resident Joonas Karhumaa visits friends in Hong Kong. He describes the last days as surreal.
- It is incredibly nice here but at the same time quite crazy. It's usually clean and nice but now it's a lot of doodles and sticky notes in some areas, he says.
Demonstrations are also underway in the Tai Po area, where Joona's friends Karhumaa lives.
- On one of the roads we saw large piles of paving stones that looked ready to be thrown. There was also a burning bus that obstructed traffic. We also saw groups of people and some had mask, they were quite young, says Joonas Karhumaa.
Yet he describes the protesters he has seen as peaceful and he has felt safe everywhere. But it seems that ordinary people are getting tired of the protests, according to Joona's Karhumaa.
- The local people I met seem to think that the protesters' demands are unreasonable and they hope that life can continue as usual, all schools are closed and some stores have empty shelves, he says.
Chinese cleaning maneuver
Saturday's clean-up maneuver, when the Chinese army sent soldiers on the streets of Hong Kong to clear barricades and debris from the huge protests held in the city, was seen by many protesters as a demonstration of power and a warning from Beijing. Saturday night became uneasy in the city, and unrest continued well into the night into Sunday.
A call on social media urges protesters to increase pressure on local government on Monday. "Get up early, target the regime, push the economy to increase the press," the call states.