Insurgents have often directed attacks at Shiite civilians, but the ministry official offered no explanation why insurgents would select the fishermen.
The attacks appeared to have been coordinated for maximum damage, and the victims were almost all Shiite civilians.
The insurgents have also radically expanded their campaign of violence to include Iraqi troops, police officers, government officials and Shiite civilians.
The local insurgents say they resent Al Qaeda's Islamic extremism and its focus on killing Shiite civilians.
Others saw him as too bound by politics, particularly as killings of Shiite civilians in mixed neighborhoods began to soar.
At a minimum, say several independent Baghdad-based analysts, the assassination kindled protests by Shiite civilians, which then led to clashes between them and security forces.
It's also because the Sunni silent majority isn't all that upset when suicide bombers blow up Jews, Christians or Shiite civilians.
But those have been small-scale gun battles with few casualties, and both groups are loyal to clerics who would never condone bombings of Shiite civilians.
Anti-Shiite feeling runs very high among jihadis in Iraq, and the murder of Shiite civilians by Sunni militants has increased.
Insurgents have often attacked Shiite civilians, apparently in an effort to provoke sectarian conflict.