Officials in Saskatchewan say there were no injuries after an explosion at a refinery rocked Regina.

The blast yesterday afternoon at the Federated Co-op refinery could be felt all around Regina and outside the city.

Police staff-sergeant Paul Tate says the explosion was similar to an incident in February, when a fire in a coker unit sent flames shooting nearly 20 metres in the air.

Fire officials say all personnel are accounted for, and the fire has been put out.

It's the fourth fire in about two years at the refinery.

In October 2011, corrosion in a pipe triggered a fireball that sent seven contract workers to hospital and forced 1,400 workers from the facility. No one was injured.

In May 2012, a much smaller fire occurred when an overheated crude oil pump ignited. There were no injuries.

Prime Minister Stephen Harper and Saskatchewan Premier Brad Wall both tweeted about the explosion.

"Glad to hear all personnel have been accounted for at the Co-Op refinery in Regina. Please stay safe EMS crews," Harper said.

Wall said: "Praying for everyone at the Co-op Refinery. Hope all are safe."