Labour Party Lawmaker Fernando Cheung who was in Sheung Wan on Sunday night during the clashes, warned on Monday that police were acting out of control.
The lawmaker had tried to negotiate between police and protesters during the clashes.
He said: "I asked the commander to allow time. Unfortunately, after I spoke, the protesters retreated, probably about 10 yards, and we had the reporters in the middle, and I saw the police fire several rounds of tear gas canisters right into the reporters, more into the reporters than into the crowd.
"I don't know what is happening, they must be out of their mind. I don't understand what the police are doing."
"I think their main purpose is to disperse the crowd. As long as the crowd leave in peace I think they've achieved their objective. So they really shouldn't cause more harm or injury," said Cheung.
He said it was ironic that police stormed into Yuen Long MTR station on Saturday night, when the previous Sunday it had been "white-shirted triads" who were indiscriminately hitting people. He said the police were doing almost exactly the same thing.
"It is really saddening to see how Hong Kong is turning into a police state. Even when the Chief Secretary came out and softly apologised for the police mishandling, the police seem to be rebelling against the Chief Secretary.
"We never see any police association voicing opposition or even using words that are close to condemning the Chief Secretary" before, Cheung said. "So I'm afraid it's really the police who are running Hong Kong."