"We hoped to block or, at least, slow down the transport of delegates toward La Malbaie, and therefore be a nuisance to the activities of the G7," the release said.
However, the group admitted that the action could only be symbolic as police managed to clear the road of about 100 protesters within an hour.
In the provincial capital of Quebec, about 100 miles southwest of the summit site, protesters managed to set two sofa couches on fire before police intervened, the Canadian Broadcasting Corporation (CBC) reported.
The G7 summit has drawn thousands of protesters to Quebec City and La Malbaie amid tight security featuring streets lined with riot police, according to images published from both cities.
Thus far, the protests were mostly peaceful with some media reports describing a carnival-like atmosphere at demonstrations.