SAINT JOHN, N.B. -- Dennis Oland pleaded not guilty Tuesday to the second-degree murder of his father, whose family built one of the Maritimes' most successful breweries, as jury selection began in a hockey arena turned into a makeshift courtroom to accommodate hundreds of prospective jurors.

Asked by Judge John Walsh of the Court of Queen's Bench to enter a plea, the 46-year-old Oland stood, leaned forward into a microphone and said "not guilty."

Oland entered his plea on Tuesday afternoon, hours after those called for jury duty stood in long lines to get into the Harbour Station arena in Saint John, N.B.

Security was tight as 5,000 summonses were initially sent out to people in Saint John and Kings counties to appear for jury duty. Many had reasons to be exempted, leaving more than 1,000 potential jurors.

Richard Oland was 69 when he was found dead in his Canterbury Street office in Saint John on July 7, 2011.

The Oland family operates Moosehead Breweries -- the oldest independently owned brewery in Canada -- although Richard Oland left the company in 1981. He went on to have a successful business career separate from the family brewery and was an active community member in Saint John.

With such a large jury pool for the trial, regional sheriff George Oram said a lot of advance planning has gone into this week's jury selection.

"It's one of the biggest we've undertaken here in Saint John and we have a lot of staff who have put in extra hours and a lot of effort has gone into this today," he said outside court.

On the concourse of Harbour Station, concession stands were open and people chatted in groups before the court convened.

One end of the floor of the arena was set-up as the courtroom. Prospective jurors were seated in the horseshoe of seats behind desks for the Crown and defence.

The trial is scheduled to begin Sept. 16 and is expected to last 65 days.

Walsh gave a lengthy explanation of how the jury selection would proceed and stressed the importance of the process.

"For many this is unnerving and inconvenient ... but this is very serious business," he said.

He explained that 1,131 people had registered for jury duty Tuesday and that a draw would be held to separate them into eight groups of roughly 142 people each.

Each prospective juror was assigned a number when they registered. A court clerk drew numbers and announced them over the public address system while they were also posted on the large score clock above centre ice.

Walsh said each group would be assigned a time to attend the courthouse in Saint John this week, starting Wednesday morning when they would start being whittled down to a jury of 12, two alternates and two triers who will assist the court in choosing the jury.

He explained the long list of reasons that could exempt someone from being chosen for the jury, such as being a relative or closely associated with anyone involved in the case: the lawyers, the accused or any of the possible witnesses.

"It is important that every juror be impartial," Walsh said.

Because of the scheduled length of the trial, Walsh said he expects a number of Fridays and other days when the court would not sit to give jurors and others a break.