Investigators are looking into any possible links with the Islamic State in Middle Eastern countries and have confirmed Abdulazeez travelled abroad more than once in 2014. He is believed to have at least visited Jordan but then he may have had family in the region.
A friend of the shooter named as Abdulrazzak Brizada by CNN claims Abdulazeez changed after his foreign trips and began to keep himself to himself. "Something happened over there, he never became close to me like he was before he went overseas. ... I'm sure he had something that happened to him overseas."
Sources said "he was born Mohammad Youssuf Saeed Hajj Ali on September 5, 1990, but that his father changed his name that year to Abdulazeez."
There appears some confusion over his original nationality but Jordan denies he was one of their nationals at any time.
But the facts are:
Abdulazeez sprayed gunfire at a joint military recruiting center in a strip mall, then drove to a Naval Reserve Center about 6 miles (10 km) away, where he killed the Marines before he himself was shot dead. Three other people were injured, including the sailor who the Navy said had died on Saturday - Reuters
At time of writing agents investigating the shootings are keeping fairly quiet about the shooter.
In time we may learn, the who, the why and more of this tragedy or act of terror; but we may never know the real truth.
This CNN report here has details of the dead.
A waitress was injured in the shooting and underwent surgery Tuesday afternoon. Her condition remains very serious. There were other casualties. All the victims plus the alleged killer were local people.
Some people in the Czech Republic keep guns for hunting but the country has tight gun laws.
But where there is a gun and the will there is the potential for a massacre.
According to official figures, Czechs own 761,000 firearms in a population - or one to every 14 Czech citizens.
If and when a person flips having a gun to hand often leads to a massacre or suicide, or like in this case both.