HONG KONG - Public transportation in Hong Kong was hit again on Monday after a weekend of sustained violence targeting facilities and inconveniencing air travelers as groups of masked protesters interfered with traveller movement at a number of metro stations on Monday, the first day of the new academic year.

At Mong Kok and Yau Ma Tei MTR stations, the busiest in Kowloon, demonstrators deliberately blocked train doors from closing and pressed emergency stop buttons at random in an attempt to hold up services. Jordan and Lai Chi Kok stations were similarly hit.

Train services along the Kwun Tong Line and Tsuen Wan Line were delayed subsequently.

Riot police patrolled key MTR stations on Monday morning and arrested a man. Several others were detained after MTR services were disrupted by demonstrators. The man was arrested in MTR's Lai King Station for alleged criminal damage in Yau Ma Tei station.

In an alert issued shortly after 8 am, the MTR said that extra traveling time was required on the Tsuen Wan and Kwun Tong subway lines. Earlier, it said that all subway lines would be operational despite vandalism on Sunday that damaged infrastructure.

Late Sunday night, Hong Kong's subway operator said facilities at 32 of its stations were "severely damaged" amid the protest, with some of these locations staying shut on Monday. Glass windows of station control rooms, ticket issuing machines, gates and security cameras were among items damaged over the weekend, MTR said. It announced around 9.30 that normal train service at Tsuen Wan was gradually resuming.

In a social media post Monday morning, Chief Executive Carrie Lam Cheng Yuet-ngor praised the MTR for having the services up and running despite more than 10 stationed being grossly vandalized by violent lawbreakers last night. She praised the professionalism of the staff of the city's sole railway operator for working overnight to repair the damage.

Protesters have called for a general strike on Monday but the city appeared to return to relative calm with shops open, trains operating and workers making their way to offices across the global financial hub.

With the tropical cyclone warning signal no.3 in force, classes of kindergartens and schools for children with physical and intellectual disability were suspended Monday. Many primary schools were closed due to the typhoon warning, reported Reuters and some older children went to school in hard hats. University students, who have often led the protests, were expected to swap classes for demonstrations later in the day.

"No, no, we're not going on strike. In these times, we need the money," said Cherry Leung, 47, told Reuters as she stacked oranges and watermelons at her street stall. "I think we've had enough trouble for now," she said.

On Sunday, efforts to interfere with traffic to and from the airport prompted some travelers to walk down the highway pushing luggage, with no buses or taxis to be seen.

On Aug 30, the MTR obtained an extension of injuction from Hong Kong's High Court seeking to bar entities from impeding operations at stations and movement of trains. With the injuction in force, violations may invite imprisonment or a fine.

With inputs from Agencies