A Canadian couple who were severely injured when they collided head-on with an SUV near Montecito remained in critical condition Thursday, according to Santa Barbara police.

Emergency crews responded to the collision in the 800 block of Old Coast Highway, near Montecito Country Club, at about 5:20 p.m. Wednesday, said Sgt. Riley Harwood.

The married couple riding the motorcycle — James Atwood, 63, and his wife, Ellen, 59, from Orangeville in Ontario, Canada — suffered major injuries, said Officer Jaycee Hunter. Both were both taken to Santa Barbara Cottage Hospital.

Authorities have said both victims are expected to survive but have very severe injuries to their left legs. Earlier reports indicated at least one of them suffered an amputated arm.

The collision occurred as the pair was following another couple from Ontario on a motorcycle westbound on Old Coast Highway, Hunter said.

When the Toyota 4Runner SUV crossed over the center line, the first motorcycle was able to swerve out of the way, but the second was struck head-on, Hunter said.

The driver of the SUV — Martin Maguire, 51, of Montecito — was arrested on felony DUI charges, said Hunter, who added that the suspect appeared to be under the influence of several substances.

Maguire was booked into Santa Barbara County Jail, with bail set at $100,000, Lt. Paul McCaffrey said.

“It’s a horrible thing,” Hunter said. “Just two couples out having fun, and the day ended in a horrific manner.”

Immediately following the collision, several bystanders rendered aid to the couple, who had shipped their Harley-Davidson bike down from Canada with the intent of taking an extended tour of the United States, McCaffrey said.

One of those bystanders, an Army soldier recently deployed in Afghanistan, “applied a tourniquet to one of the injured riders that possibly saved their life due to massive bleeding,” he said.

Old Coast Highway was closed for several hours while the wreck was being investigated and the wreckage cleared.

Noozhawk staff writer Gina Potthoff can be reached at gpotthoff@noozhawk.com. Follow Noozhawk on Twitter: @noozhawk, @NoozhawkNews and @NoozhawkBiz. Connect with Noozhawk on Facebook.