Ania Wliczewski says her black eye was caused by Vancouver police while she recorded an altercation on her cellphone. (CBC)

A woman who alleges she and a friend were assaulted by Vancouver police officers says she chose not to call 911 because she didn't think her side of the story would be believed.

Ania Wilczewski said the incident began as she and Caitlin Buxton saw Vancouver police officers involved in an altercation with a man outside a Gastown nightclub the night of Aug. 17.

Rather than call the emergency phone number, she used her cellphone to make a video recording of what was occurring, and that's when she and Buxton were tackled and arrested, Wilczewski told CBC News on Friday.

"There was police already at the scene," Wilczewski said. "They were already there and they were the ones who did something wrong."

Wilczewski said she was stunned to see the video was no longer on her cellphone when police returned it after she and Buxton were released from custody Tuesday morning.

She was left with was a black eye and bruised ribs, Wilczewski said.

Buxton said her wrists and head were injured during the incident.

Caitlin Buxton, left, and Ania Wliczewski outside Vancouver club where they say police assaulted them. (CBC)

"I can't bend [my wrists] very well and this whole side of my head is bruised," said Buxton, pointing to her left temple.

Police would follow up on the women's allegations, Const. Jana McGuinness told a news conference at the department's headquarters Friday.

McGuinness also said people should always feel confident they can get help when they call 911.

"We have a very good reputation of being an open, transparent police department," McGuinness said.

"We think that in this situation and any others in the future, people will call the police if they do witness something like that," the constable said.

The women said they would consult a lawyer and likely file a complaint against the police officers involved.

The cellphone is now in the hands of a technician hired by CBC to see if the video can be recovered and if the women's story can be substantiated, according to CBC Vancouver news director Wayne Williams.