BRAMPTON, Ont. - Crippling Canada's infrastructure and leaving its population devastated were the goals of an alleged homegrown terror cell, a jury was told Monday as the final trial in the so-called Toronto 18 case heard opening arguments.

Parliament, power grids, and nuclear facilities were the intended targets in an attack that Fahim Ahmad hoped Canada would never recover from, the Crown said as it laid out its case against three men arrested almost four years ago.

Three men are on trial, charged with various terrorism offences, but at the heart of the plot were the machinations of one man plotting destruction, said Crown attorney Iona Jaffe.

"This trial is about a man named Fahim Ahmad, who the Crown alleges led the terrorist group and about some of the men who helped him," Jaffe told the five-woman, seven-man jury.

Ahmad, 25, Asad Ansari, 25, and Steven Chand, 29, were arrested in June 2006 in a police sweep that captured headlines around the world. They pleaded not guilty to their charges in court Monday.

All three are charged with participating in a terrorist group. Ahmad is also charged with instructing people to carry out activities for a terrorist group and a weapons offence. Chand also faces a charge of counselling to commit fraud over $5,000 for the benefit of a terrorist group.

Canada's spy agency sent informant Mubin Shaikh to a banquet hall in November 2005 for a presentation on security certificates and told him to get close to Ahmad and others.

"Fahim Ahmad began to talk about his plans to strike specific Canadian targets: Parliament, electrical grids, nuclear stations," Jaffe told the jury.

"He wanted to cripple Canadian infrastructure."

Ahmad also later told Shaikh he had military targets in mind and specifically wanted to attack the nuclear plant in Pickering, Ont., Shaikh said.

Observing the behaviour of a group of about half a dozen people sitting at a table in the banquet hall, everyone seemed to be deferring to Ahmad, Shaikh testified as the Crown's first witness.

"It was clear to me that Fahim was definitely the leader of the group," he said.

Outside the banquet hall Ahmad hugged him and Shaikh could feel something hard in Ahmad's pocket, he testified. Shaikh heard the sound of a gun's magazine being released and pulled out and Ahmad showed it to him with the top round exposed, Shaikh said.

"These are cop killer bullets," Shaikh said Ahmad told him.

The Crown said it will call evidence to show Ahmad led two training camps to prepare people to carry out terrorist attacks. At the first attendees took part in military-type activities, obstacle courses and target practice with real and paintball guns, Jaffe said.

At the camp in Washago, Ont., north of Toronto, in December 2005 Ahmad gave a speech saying, "it doesn't matter the trials you face, it doesn't matter, what comes your way. Our mission is greater," Jaffe said.

"This has to get done," Jaffe quotes Ahmad as saying. "Rome has to be defeated and we have to be the ones that do it. No holding back. No matter if it's one man that survives, you have to do it...God willing, we will get victory."

Ahmad, Ansari and Chand were among 18 people arrested. Seven people had their charges dropped or stayed, two people were convicted after trials and six people pleaded guilty.

The Crown intends to call up to 11 witnesses, most of whom will be police officers, and play for the jury about 70 wiretap conversations.

In one of those, Ahmad is heard saying the kind of attack he was planning has "never been done before," Jaffe said.

"They're probably expecting what happened in London or something," Ahmad said, referring to co-ordinated suicide bomb attacks in July 2005 in London's subway system that killed 52 people and injured nearly 800.

"Our thing is much, much greater on the scale. You do it once and you make sure they never recover again."

The "first chapter" of this story begins in August 2005, Jaffe said, when two men entering Canada from the U.S. were stopped at the border in Niagara carrying three semi-automatic guns -- hidden in their waistbands and taped to their thighs. They were driving a rental car paid for using Ahmad's credit card, he added.

Ahmad had telephone conversations with one of those men while he was in prison and also sent him a package with books and MP3s, including one titled "The Constants of Jihad," Jaffe said.