The Hong Kong police have confirmed that they received intelligence and formed a team before the violent mob attacks in Yuen Long last Sunday, but decided it would be of low risk.
On Sunday night, a group of unknown men in white attacked people at the MTR station with bamboo sticks and metal bars, among other weapons. The incident left at least 45 people injured including journalists and a lawmaker. At least twelve have since been arrested, including some with triad backgrounds.
Police confirmed they received information from Yuen Long district councillor Johnny Mak on Sunday morning suggesting that triads may mobilise to attack residents who came back from the anti-extradition law march that day. A team was formed at 6pm to handle the potential incident.

During their press conference on Thursday, police also confirmed details of the riot police deployment on Sunday in Sheung Wan. Officers cleared protesters on Hong Kong Island who were retreating to Central after demonstrating outside the China Liaison Office in Sai Wan.
Police said they used 55 cans of tear gas, five rounds of rubber bullets and 24 sponge grenades. Sponge grenades are a bullet-shaped crowd control projectile weapon.
Anthony Tsang, the acting New Territories North regional commander, said at a press conference on Thursday that the situation in Sheung Wan was serious, but Yuen Long was of lower risk.
“The district councillor also told us that people were not coming [to Yuen Long], so it was not so urgent to send officers in,” Tsang said.

Tsang said the police tried their utmost to deal with the incident: “We understand that the operation and the result on that day may have been slightly worse than what the public would expect. We are very saddened for we could not stop the incident causing injuries in time,” he said.
“As the New Territories North regional commander, I can assure you that the police have the determination to maintain Hong Kong’s order and protect our residents.”

The police received reports from Yuen Long at 10:41pm on Sunday. Two uniformed officers arrived eleven minutes later and observed the attacks. They decided to go to a safer location and wait for assistance, even though they had firearms.

Tsang defended the decision as appropriate and said reinforcements came quickly at 11:20pm. When asked whether a 40-minute period was too long a wait for reinforcements, Tsang said he didn’t believe it was 40 minutes.
However, after speaking with an officer next to him at the press conference he said: “Oh, it was 39 minutes… We may need to review our personnel arrangements.”
【上環開槍無人講?】【整合傳媒片段】21-07-2019示威者淪為活靶警員無警示下橋上開槍片段來源:香港獨立媒體網、Now News – 新聞【有片!上環開槍詳細片段:】https://www.facebook.com/FTVV612/videos/397893927515224/____________________相關資料:警方驅散干諾道西示威者 天橋上無預警下向人群開槍https://www.facebook.com/inmediahk/videos/1307851056040490/?v=1307851056040490721警方上環驅散示威者未有示警橋上開槍https://news.now.com/home/local/player?newsId=356494&fbclid=IwAR2EcXDW6Lib8RMIHV_yZflmyEEVDit81dfVfNtIzllv2VoLJzbEiZQXDj8
Posted by FTVV on Tuesday, 23 July 2019
During the Sheung Wan clearance, footage from multiple news channels apparently showed that an officer shot sponge grenades at protesters from a bridge above them, without prior warning.
John Tse, chief superintendent of the Police Public Relations Branch, said officers made “umbrella-form warnings” by raising a black flag – warning tear gas will be used. They also broadcast messages, instead of giving new warnings every time officers shot weapons.
Tse said he believed officers saw people below the bridge had tried to throw bricks, and thus an officer shot a sponge grenade at a protester below.