John Stewart Nuttall and Amanda Marie Korody were arrested Monday, Royal Canadian Mounted Police Assistant Commissioner James Malizia said at a press conference. They have been charged with conspiracy, facilitating a terrorist activity and making an explosive device.
Authorities say Nuttall and Korody attempted to leave a suspicious package at British Columbia's provincial legislature on Canada Day, celebrated Monday.
Photographs released by the RCMP show that three pressure cookers, similar to the pressure cooker devices used to house explosives in the Boston Marathon bombing in April, are among the evidence. The bombings in Boston killed three and injured more than 260 others.
Police say the alleged plot was influenced by al Qaeda ideology, but called it a domestic threat with no connections to groups overseas. Police also said the public was never at risk and the threat was detected early.
"I want to reassure our citizens that at all times during the investigation, our primary focus was the safety and protection of the public," Malizia said. "While the RCMP believes this threat was real, at no time was the security of the public at risk."
RCMP Assistant Commissioner Wayne Rideout said that the devices in the alleged plot were "completely under our control, they were inert."
ABC News and the Associated Press contributed to this report.