BRAMPTON, Ont. - A young man was "duped" into being part of a terrorist plot to bomb Canadian targets and had virtually no knowledge of the scale of the plan, a lawyer said Monday about his client who nonetheless pleaded guilty to terrorism offences.

Saad Gaya, 21, pleaded guilty to intending to cause an explosion for the benefit of a terrorist group. He was among 18 men and youths rounded up in 2006 and charged in a plot to wreak havoc on several targets, including Parliament and RCMP headquarters.

He is now the third member of the so-called Toronto 18 to plead guilty.

Gaya pleaded guilty because "it's the right thing to do," his lawyer Paul Slansky said outside court. Slansky described Gaya as a relatively minor member of the bomb plot who has expressed remorse to him.

"To some extent he was duped," Slansky said.

"Certain people had certain plans that were not communicated to Mr. Gaya and Mr. Gaya will be taking the position that he did not know their plans."

"He in fact had asked for assurances that there would not be harm to people."

An agreed statement of facts was entered as an exhibit and will be read into the court record at Gaya's sentencing hearing, which is scheduled for Dec. 21 to 23. He is scheduled to be sentenced Jan. 6.

The statement details how those involved in the domestic terror plot were planning to bomb Canadian targets such as RCMP headquarters and nuclear facilities, attack Parliament and take hostages.

Gaya and Saad Khalid were arrested while unloading bags labelled "ammonium nitrate" from a truck driven by an undercover police officer.

Khalid, 23, pleaded guilty in May and earlier this month was given a 14-year prison sentence. Last week, Ali Dirie, 26, pleaded guilty to his role in the plot and faces a maximum 10-year sentence.

But Gaya did not have knowledge of the magnitude of the explosive force of the purported ammonium nitrate, nor did he know the group's alleged leaders intended for him to drive a van loaded with fertilizer bombs, according to the agreed statement of facts, which also contained a transcript of Gaya's post-arrest police interview.

Gaya was 18 at the time and his youth is illustrated by the transcript in which he says "I wasn't told anything specific but I can make I could put two and two together, you know what I meana like I had ideas causing like you know, something big...uh you know what I mean."

In the interview he says the goal of the explosions was to pressure Canada to withdraw its troops from Afghanistan.

"Like how one person, only one person, you can like, make a change for like so many thousands of lives uh for all the other people are being oppressed maybe you're that one person that God has chosen that's gonna make a difference so maybe you should help out," Gaya said in the June 2006 interview.

"And to be that one person who can change, like, everything. And it just kinda, I don't know, like, I...I thought it was...some...sort of like way of like fixing things."

Slansky said he believes Khalid - who was given seven years credit for pre-trial custody and can apply for parole after less than 2 1/2 years - to be more involved in the plot than Gaya, and that it should be reflected in sentencing.

"I think it would be highly unusual for my client to get a sentence as much as Mr. Khalid got," Slansky said.

"He probably would get somewhat less, maybe significantly less."

Slansky didn't say the exact sentence he would be seeking. While he said a jail sentence is "obviously" appropriate, Slansky noted Gaya has been in custody for more than three years - as long as Khalid - and one of those years was in isolation, for which Slansky said he would be seeking additional credit.

Gaya's family attended court for his guilty plea but did not want to comment.

Only one case involving the Toronto 18 has gone to trial so far, resulting in a conviction.

Last September, a judge found Nishanthan Yogakrishnan guilty of participating in, and contributing to, a terrorist group.

Although 17 at the time of the offences, he was tried as a youth but received an adult sentence of 2 1/2 years before being released in May in light of his time served before trial.

In the summer of 2006, an intense investigation involving Canada's spy agency and the RCMP ended with the arrests of 18 people in the Toronto area and the seizure of apparent bomb-making materials.

The case took a stunning turn when allegations surfaced that the ringleaders had talked about plans to storm Parliament, take MPs hostage and behead the prime minister.