Another MTR train has been covered in graffiti by guerrilla artists.

According to an MTR source cited by Apple Daily, one of the trains on the East Rail line train was spray painted by unknown persons sometime between Sunday night and early Monday morning.

Photo: Apple Daily.

Local media reported that, as the train was needed to transport passengers during peak times, it was used at around 7am on Monday morning, and was called back to the depot to have the graffiti washed off afterwards.

Photos posted on social media showed the train holding passengers at Fo Tan station and on an outdoor platform at another station. The source told Apple Daily that the MTR Corporation had increased security patrols after an American couple going by the pseudonyms Utah and Ether snuck into depots in Hong Kong and graffitied MTR trains on three occasions.

According to the MTRC, the damage took place between 2011 and 2015, but the public only learned of their actions after they released a video in 2016. The clip promoted the release of a book about their adventures painting subways in Asia.

According to Vice, the artists – whose real names are Danielle Bremner and Jim Clay Harper – were temporarily separated in 2016 when Harper received a six-month jail sentence in Australia.