Proceedings in an Edmonton courtroom came to an abrupt halt Friday morning when a man attacked the accused in a double murder trial.

Michael Briscoe, who is on trial in the 2005 murders of Nina Courtepatte and Ellie May Meyer, was attacked by the man as he sat in the prisoner's box listening to arguments.

Michael Briscoe, on trial for two murders, was attacked in court Friday. (CBC)

Briscoe's lawyer and the Crown prosecutor were discussing whether certain evidence was admissable, when a man leapt over the partition separating the gallery from the court.

"All of a sudden a big huge guy jumped over the railing," said David Macleod, a police studies student at Grant MacEwan University who was in the courtroom.

The man ran at Briscoe who moved backwards, but ended up toppling over the box onto his head while the man grabbed at his throat.

The sheriff and Briscoe's lawyer Charles Davison managed to get a hold of the man, wrestling him to the ground and calling for help.

"He was a very big man," he said. "It was quite a few minutes before any other sheriffs came in."

Briscoe appeared to have some bruising to his neck, but told the court he was ready to continue Friday afternoon.

The man was taken into custody.

Briscoe's trial is scheduled for another five weeks.