After 4 years, more information about #721YuenLongTerrorAttack has been revealed as the trial against Lam Cheuk-ting, a former democratic lawmaker who claimed to be there to understand the situation.
Witness B, who was a staff at the station time, said that police contacted the station through whatsapp to send 2 police to monitor the station on July 19th, 2 days before the attack.
On 20th, police arranged to have 2 police to standby at the monitor room starting at 5:00PM on 21st.
There were 2 police in the monitor room during the attack on 21st.
Clearly, #HKPolice knew that the local thugs had planned the attack 2 days before the incident.
https://t.me/appledailyhk26
https://t.me/hkerappledaily2