A Mississauga, Ont., teacher is being investigated by the Dufferin-Peel Catholic District School Board after she spoke at a rally in early July urging Palestinians to fight back against Israel and making what critics have called supportive statements about people linked to a group that Canada lists as a terrorist entity.

Nadia Shoufani, a teacher at St. Catherine of Siena Separate School in Mississauga, called Ghassan Kanafani, a Palestinian writer killed in 1972, a "martyr," and criticized the detention of Georges Ibrahim Abdallah, a Lebanese militant imprisoned in France for killing two U.S. and Israeli officials.

Both are linked to the Popular Front for the Liberation of Palestine.

"Palestine will be liberated. Glory to the martyrs," she said to a crowd at the International Al-Quds Day rally on July 2 behind Queen's Park in Toronto. "We have the right to fight back. We have the right to resist," she said. 

Bruce Campbell, general manager of communications and community relations for the Dufferin-Peel Catholic District School Board, said Wednesday an investigation has begun. He said the matter was brought to the board's attention through a number of sources, including the Friends of Simon Wiesenthal Center and B'nai Brith Canada.

"The board was made aware of this issue last week and is investigating," Campbell said. "Given the serious nature of the issue, we would look to reach a resolution as quickly as possible."

You can watch Nadia Shoufani speak at the Toronto Al-Quds Rally in video below.

Toronto police said they have opened an investigation into comments made at the Al-Quds rally, but could not confirm that Shoufani herself is under investigation.

"It's being investigated as we speak," Const. Allyson Douglas-Cook said on Wednesday. "I can confirm that we are investigating comments made at the rally and there is more than one person involved."

CBC News has reached out to Shoufani for comment, but has not been able to reach her.

Ann Hawkins, president of OECTA, the union for teachers in Ontario's Catholic education system, said Thursday it will be representing Shoufani during the school board's investigation. 

Hawkins could not comment on the status of the investigation or what discipline, if any, could result. She also could not speak to whether Shoufani had been the subject of an investigation in the past.

A spokesperson for the Ontario College of Teachers said the organization is "aware of the matter.

"If and when a complaint is launched to the College, we will deal with it accordingly," Gabrielle Barkany said in an email to CBC News.

Shoufani is in good standing with the College, Barkany said.

Amanda Hohmann, national director of the League for Human Rights for B'nai Brith Canada, said on Wednesday the organization complained to the board and the police last week because it alleges that Shoufani is publicly supporting violence and terrorism.

She said it is also inappropriate for a teacher to be espousing such views when she is responsible for educating children.

B'nai Brith concerned

"We're obviously very concerned about the potential for radicalization, the messaging, and the ideology that someone is spreading when they are involved in educating children," Hohmann said.

According to Public Safety Canada, the goals of the Popular Front for the Liberation of Palestine, formed in 1967, are the destruction of Israel and the establishment of a communist government in the Palestinian territories.

Public Safety Canada said the group hijacked three civilian airliners in 1970s and has used suicide bombers, guerrilla tactics, car bombings and mortar strikes to further its aims since 2000. It said the group was also responsible for the first assassination of a cabinet minister in Israel's history, killing Tourism Minister Rehavam Zeevi in 2001.