A massive bomb exploded at a government office in Oslo, Norway, on Friday, killing at least seven people and injuring dozens of others. Though the building houses Prime Minister Jens Stoltenberg's office, he was unharmed. Little more than two hours after the explosion, Norway was gripped by a shooting at a youth camp on a nearby island. Unconfirmed reports indicate as many as 20 deaths at that scene. As of early Friday afternoon, police and investigators have not been able to confirm who was behind the two events, but many people are blaming al Qaeda — citing a 2010 incident in which three men with alleged ties to the terror group were arrested, two of them in Norway, over a plotted terrorist attack. In the Dubai Al Arabiya, Ray Moseley recounts other reasons why the world's best-known terror organization is a likely culprit in Friday's assaults. It's possible al Qaeda was acting on past threats to retaliate if Norway didn't withdraw its 500 troops from Afghanistan. Or perhaps al Qaeda is still angry over "the 2010 publication in the Oslo newspaper Dagbladet of a cartoon showing the Prophet Muhammad as a pig writing the Quran." That led 1,000 Muslim taxi drivers to block the streets of central Oslo in February 2010. What else might be a factor? Here, an excerpt:

Yet another possibility is that the bombing was linked to a controversy over Mullah Krekar, founder of the Kurdish armed Islamist group Ansar al-Islam. Norwegian prosecutors filed a terrorism charge against him on Tuesday after he threatened a former minister, Erna Solberg, with death if he is deported....

In 2009 he announced he wanted to establish an Islamic Caliphate with Osama bin Laden as one of its leaders.

Read the entire article in Al Arabiya.