How safe should you feel riding the Toronto subway, the Montreal Metro or Vancouver's SkyTrain?
It's a legitimate question after a crude bomb was discovered on a section of SkyTrain track on Friday.
RCMP removed the device — empty gas canisters attached to what looked like a small fire extinguisher with wires sticking out of it — from a section of line in suburban Surrey after a passenger reported it.
It's not clear it would have gone off but Transit Police spokeswoman Anne Drennan told the Vancouver Sun the elevated SkyTrain guideway is designed to withstand an earthquake, which would have helped reduce the damage of an explosion.
[ Related: Pipe bomb prompts inspection of B.C. SkyTrain system ]
As the 2004 bombings of Madrid's commuter-rail system that killed 191 people and injured 1,800 demonstrated, mass transit is particularly vulnerable to attack. Kilometres of rail lines, packed trains and crowded station platforms make inviting targets for terrorists.
A year later, 52 people died when suicide bombers detonated explosives in three London Underground trains and a double-decker bus.
Hardening such systems to minimize the threat is costly and carries the prospect of reducing their efficiency at moving people.
The odds of transit systems in Vancouver, Toronto or Montreal — or Calgary and Edmonton's light-rail systems for that matter — being targets of organized attacks are probably low. But Friday's incident demonstrated they're far from non-existent.
Toronto Transit Commission officials were warned last month that extending mobile-phone service to underground subway stations and tunnels poses a potential security threat.
Terrorism expert David Harris told the Toronto Sun that cellphone networks are commonly used by terrorists to detonate explosives remotely.
"If (the TTC) hasn't taken … seriously this possibility into account, then someone isn't doing their job," Harris said.
"I think this would certainly facilitate a terrorist operation, and particularly with regards to the remote triggering of devices."
In June 2010, days before the G20 summit, Toronto's subway service was disrupted for almost an hour after a suspicious package was reported at one station. It turned out to be an unattended suitcase.
And last May, a series of smoke-bomb attacks, possibly linked to protests over the Quebec government's planned university tuition hikes, shut down Montreal's Metro system during the morning rush hour.
Transit police and other security officers were more in evidence along Vancouver's SkyTrain lines on Monday.
"We are continuing with our sweeps of all of the stations, bus loops and terminals," Drennan told the Sun. "We are also riding the trains wherever possible, doing sweeps of all of the buses and cars."
The SkyTrain system, which handles about 250,000 riders on an average weekday, will maintain additional police and security coverage at stations and on trains for the first half of the week in part to send a message to riders.
"This is to assist in site security, site sweeps and also to reassure passengers that we're taking this very seriously and that their safety is our No 1 priority," Drennan told the Sun.
The bomb discovery Friday, followed by a couple of false alarms, shut down part of the SkyTrain system for three hours, CBC News said.
Criminologist Darryl Plecas told QMI Agency the bomb was not likely the work of an organized terror group.
"It's not the work of a very sophisticated person,'' said Plecas, director of the centre for criminal justice research at the University of the Fraser Valley. "It could be somebody that's angry at transit.''
Meanwhile, the Sun reported, search teams were combing all 134 kilometres of track along Metro Vancouver's three lines, as well as 57 SkyTrain stations, three bridges and three tunnels to look for more explosives.
(Photo courtesy of CBC)