Alex was among the 45 people arrested after hundreds of police poured onto Lung Wo Road to stop protesters who had built barricades.

Besides Alex, police rounded up several people in nearby Tamar Park. Police have launched an inquiry after a television crew filmed one man being kicked by at least seven officers.

Another protester who was arrested, Issac Tong, 24, said he suffered injuries to his head, back and ankles during his arrest. Another protester, a 20-year-old, said he was kicked in the head and hit with a baton by four or five officers.

Alex yesterday described himself as "scared and angry at the moment, but now overwhelmed with sadness and extreme disappointment at the police force". Veins in his left eyeball had burst.

He had scratches on his nose and cheeks, a lump on the left side of his head, baton marks on his left arm and bruises on his left knee.

Alex also said bruises were forming on his inner right thigh, after a police officer allegedly kneed him close to his groin.

"Mixing their emotions with the force and power they have, it's dangerous," he said. "They crossed the line, and now they are no longer a police force, but just a group of legally permitted thugs."

Alex, a third-year politics university student , said he took part in the civil disobedience movement because it was time to push for a democratic process in Hong Kong.

He said he urged protesters to "not forget what they are fighting for" and to remember the pacifist nature of the movement.

The alleged brutal police treatment stunned him. He said he was first arrested on July 2, along with 500 others, during a sit-in on Chater Road that targeted the white paper from Beijing denying Hong Kong its promised "high degree of autonomy".

On Wednesday, Alex said he thought the police handled that situation professionally.

He said his alleged beating in the park was carried out by at least four officers while he was blinded by pepper spray. Police swore and insulted him the whole time, he claimed. "I felt like a rabbit surrounded by wolves," he said.

The insults continued in the police car, he said, as officers laughed at his face covered in mucus, dirt and the orange gel from the spray.

Alex said he was taken to Wong Chuk Hang Police Station and later to North Point Police Station before being freed late on Wednesday night.

Tong, who was also arrested on July 2, said that on Wednesday, he was hauled away face down, his ankles dragging along the ground. The officers "were hitting my legs with batons while they were dragging me to a dark corner", he claimed.

The alleged beating, he said, took about four minutes. He suffered a dislocated joint in his right arm and said he "couldn't feel his legs" afterwards.

Tong said he waited for more than four hours before being taken to Ruttonjee Hospital to be examined.

He said the alleged police brutality he experienced would not stop him from returning to support Occupy protests.

A 20-year-old protester, who was among those who dashed onto Lung Wo Road, said he sustained injuries to his forehead, neck and ankle.

The man, who gave only his surname of Au, clamed he was kicked in the head and hit by the batons of several police. During his detention, he said, officers accused him of being a triad member.

He said he never provoked the officers and held only an umbrella. "They tried very hard several times to pull my necklace and mask off my neck," he said.

Au, who works full time as a waiter, said that during his 20-hour detention, police asked him if he was paid and which triad gang he belonged to.