Clean-up efforts are underway after a barge carrying hundreds of scrap cars suddenly tipped over Friday afternoon, spilling dozens of wrecked vehicles into a Victoria harbour.

An oily slick covered the water’s surface at Victoria’s inner harbour, but according to a Ministry of Environment official, there is no substantial environmental damage.

"From what we've seen, there's minimal on-water hydrocarbons or pollution," Laurie Boyle, an emergency response officer with the Ministry of Environment, told CTV Vancouver.

The vehicles were cleaned of fuel before being loaded onto the barge, preventing any significant oil spill. The pre-travel clean-up is mandatory for auto-recycling facilities under the B.C. Auto Recyclers’ Regulation, Boyle said.

Booms were placed in the harbour to prevent polluted water from spreading. The ministry said as many as 20 vehicles fell into the water, but witnesses put the number closer to 50.

Witnesses reported hearing a loud noise before the vessel tipped over.

No one was injured in the incident, officials said. The cause of the spill is still unclear.

Worksafe B.C. and city officials were on site to provide support for clean-up crews along the shore, according to a city statement.

The vessel is owned by Seaspan Marine and was en route to a Washington port before the incident, according to Bart Reynolds, president of the company.

"I can't comment on who's responsible for what at this stage,” Reynolds told CTV Vancouver on Friday. "We don't have full details on what happened. The barge is currently listing hard against the dock. We believe it's hard grounded at this point."

Schnitzer Steel is the American company that recycles the cars. The company has declined to answer any questions about the incident.

Workers were expected to wait for the tide to drop before unloading the remaining vehicles from the barge.

B.C. follows the “polluter-pay” model when it comes to industrial accidents that cause environmental damage. That means the party responsible for accident has to pay for the required cleanup and environmental recovery efforts.

No fines will be laid in connection with the incident until investigators determine the cause of the spill.