This charred wreck may be the remains of a car bomb that detonated outside the Norwegian prime minister’s office in Oslo. Could terrorists have succeeded in Norway where last year’s would-be Times Square bomber failed?

Details of Friday’s attack in Oslo are scant. Initial reports are vague and incomplete. Local police have confirmed a blast that damaged several Oslo buildings and killed at least one person — a toll expected to rise — was the result of a bomb. Norwegian TV is showing images of this car as a potential source of the bombing. Some reports indicate there may be a second bomb-packed car.

As of this writing, there don’t appear to be body parts around the hulk of the car, or other indications that it was set off by a suicide driver. That would indicate the style of attack aped that of would-be Times Square bomber Faisal Shahzad, who loaded an SUV with fireworks, gas and propane, ignited the device and walked away, expecting the car to detonate.

“That’s been so common that it’s not necessarily so sophisticated,” says Hank Crumpton, the former State Department counterterrorism chief. “Hezbollah’s used both suicide driver & remote detonations. Oklahoma City was remotely detonated, no suicide driver.”

Except that this is the first time a car bomb — a signature weapon of the Iraq and Afghanistan wars — has targeted Oslo. It may be paired with another attack, as reports are coming in of a gunman dressed as a police officer shooting up a youth conference for Norway’s Labour Party on Utoya Island. Simultaneous “complex” attacks — those that use a mixture of tactics — are the hallmark of al-Qaida and aligned terrorists.

Car bombs are most often used to drive up to a target and attack it. But not always: the first World Trade Center bombing came from a parked van stuffed with explosives. Parked car bombs avoid the operational difficulty of planting a bomb inside a building.

Evan Kohlmann, a terrorism analyst, says that on the extremist Shamukh forum, a user named Amir Grozny posted a warning that Norway will see “blood running in the streets” if it doesn’t withdraw its 400 troops from Afghanistan. “Norway has had an increasing problem with these kind of asymmetric threats from al-Qaida and its Central Asian allies,” Kohlmann says. “Amir Grozny is a user who appears to be from the Caucasus originally, now fighting in Afghanistan.”

At least one organization asserts confidently that a car bomb was the cause of Friday’s devastation: the Pentagon’s bomb squad, known as JIEDDO. It tweeted a reminder that vehicle-borne improvised explosive devices, or VBIEDs, are the “third most common” type of homemade bombs — and that insurgents and terrorists plant an average of 553 homemade bombs each month, worldwide.

One potential culprit is Mullah Krekar, an Iraqi Kurdish extremist and founder of the al-Qaida-aligned Ansar al-Islam who’s lived in Norway for years. Krekar was recently charged with terrorism-related crimes for threatening attacks against Norway if immigration officials deport him.

Jim Arkedis, a former Defense Department counterterrorism analyst who focused on Europe, guesses that the actual perpetrators are a “relatively isolated cell that formed on its own,” with “tangential links” to established jihadi organizations. That, at least, was the modus operandi of the cells responsible for the 2004 attack on Madrid and the 2005 attack on London. A car bomb is less sophisticated than either of those attacks — multiple suicide bombers simultaneously attacking packed mass transit — but, Arkedis says, getting at least one car bomb into a secure area is “typically more complex on the operational side than convincing a young kid that a bombing is worth his life.”

For more on the Oslo bombings, check out the Twitter hashtags #Oslo, #osloblast, #osloexpl, and #oslobomb.

Update, 1:40 p.m.: Reuters reports that the death toll has risen to seven.