In Tuen Mun a crowd of several hundred protesters gathered, at one point battling with the police and pushing them back by throwing all manner of objects at them.
Officers were briefly cornered before they retreated inside a building. The protesters later scarpered after seeing more police carrying guns arriving.
But the standoffs continued, with tear gas fired at protesters blocking roads.
Meanwhile, officers fired multiple rounds of tear gas at a crowd of hundreds in Wong Tai Sin who had formed a defensive line using umbrellas and other objects.
The protesters, some geared up with bamboo sticks, later regrouped on Sheung Fung Street where a new standoff with the police ensued.
Hundreds of people later blocked traffic on Po Kong Village Road.
Elsewhere, hundreds of people marched along Cheung Sha Wan Road in Sham Shui Po, chanting protest slogans as they went. When they got to Wong Chuk Street, they dismantled railings to use as barricades to block the road.
Police later charged down the road at them, and the protesters fled into various nearby streets.
But after police retreated, the protesters regrouped, blocking the intersection of Cheung Sha Wan Road and Yen Chow Street. The crowd set objects on fire outside the Cheung Sha Wan Government Offices.
A group of protesters set fire to objects outside an office of China Travel Service in Tsuen Wan, and sprayed paint outside a branch of the Bank of China. They later set up barricades on Castle Peak Road.
In Sha Tin, hundreds headed to towards Siu Lek Yuen following a rally at Che Kung Temple. Tear gas was also later fired in the district after protesters set up a road blockade.
Black-clad protesters had also packed into Southorn Playground in Wan Chai, later streaming out to block nearby Luard Road using rubbish bins.
The Wan Chai crowd then swelled the ranks of the thousands of marchers who had set off from Causeway Bay bound for Central.
Last updated: 2019-10-01 HKT 16:13