A pod of killer whales swam past Stanley Park and under the Lions Gate Bridge and into Vancouver Harbour on Friday, sparking a flurry of photos on Twitter and other social media.

The Vancouver Aquarium says as many as eight whales were swimming and breaching in the waters this afternoon.

Jen Derwojed, who works at the aquarium, said they were transient killer whales that were probably looking for food.

"We saw two families of transient killer whales. These are the kind that hunt marine mammals and there were two very large males and a few juveniles," she said.

The whales turned around just before the Iron Workers Memorial Bridge and Derwojed said crews from the aquarium followed them to Howe Sound.

This is the fourth year in a row whales have shown up in the waters around Metro Vancouver. Killer whales were spotted near Jericho Beach in 2012 and in the harbour in 2011. In 2010, a grey whale swam into False Creek.