Approximately nine cars derailed near downtown Slave Lake, Alta., Thursday afternoon.

Mayor Tyler Warman told CBC News the derailment happened around 4 p.m. along the CN rail line just off Main Street, about one block from the town office.

Witnesses said the cars were mostly carrying grain and no nearby buildings were damaged. 

Emergency personnel are currently on scene, Warman said, and six residences have been evacuated close to the site as a precautionary measure. 

"We have no indication that there have been any injuries or any dangerous goods spilled at this time," said Warmon.

"Obviously, it could have been a lot worse." 

The derailment comes 6-months after residents in Slave Lake met with CN officials to discuss concerns they had over the line's safety in the wake of derailments in Gainford and Peers, Alta.

"We've had a lot of lengthy discussions with CN," said Warman. "They went over their procedures and policies, how they deal with their day-to-day business and a lot of the safety precautions they have in place. It left us feeling a little more reassured.

"Obviously with this recent derailment, it definitely has us questioning some of that." 

Two trains go through the town each day which, in total, transport 56,000 cars full of dangerous goods annually.

A few roads near the derailment are still blocked off. 

Warman said CN staff are on site now and more crews are coming from Edmonton.

"The cleanup will commence and we'll get back to day-to-day business and then look at what we have to do in the future to make sure this doesn't happen again."