Two men are in custody after a sheriff was wounded in the hand during a shooting inside a Whitecourt, Alta., courthouse northwest of Edmonton Tuesday morning.

The shooting suspect, who was a prisoner at the courthouse, escaped with a second prisoner in a sheriff's van, according to Kathlene Campbell-Conlon, a reporter who was present.

She said the sheriff jumped over a barrier in the courtroom, responding to a fight that broke out just outside the courtroom doors.

She heard high-pitched screams and what she thought were three gunshots, she said.

"I have never in my life heard a gunshot before," said Campbell-Conlon.

That's when most people ran from the courthouse, she said, and that's where she saw the suspects hop into a sheriff's van and drive away.

Reporter Kathlene Campbell-Conlon was in the courtroom when she heard an altercation followed by gunshots. (CBC)

Campbell-Conlon said people were calling 911 for an officer who had been shot.

"It was just terrifying," she said.

Two suspects were later apprehended at a rural property on Highway 32 outside of Whitecourt. Police later ruled out the possibility of a third suspect.

Whitecourt detachment commander Staff Sgt. Rodney Koscielny said earlier that police searched buildings on the property to make sure no other prisoners are at large.

He said shots may have been fired at the second scene on the highway.

“This is over the top,” Koscielny said. “We’re here to protect the public and something like that affects us all, including the public. So yes, it is very serious.”

The local radio station reported that police set up roadblocks in the area. All the schools in Whitecourt, the courthouse and town offices were locked down as a result of the shooting.

RCMP confirm that the suspects were among those arrested last Thursday in a drug bust in the community.

RCMP officers stand guard at the Whitecourt provincial courthouse after a shooting Tuesday morning. (Marion Warnica/CBC News)

The Whitecourt courthouse doesn't have a metal detector at the door and Mayor Trevor Thain suggests Tuesday's incident should prompt a review.

"I think the [solicitor general] will have to take a look at the security at the courthouse," he said.

"You know maybe there needs to be a look at what the rules and regulations are in the transport of prisoners."

Whitecourt is 180 kilometres northwest of Edmonton.

With files from The Canadian Press