The bomber detonated a small tanker truck at the home of police Brigadier General Ismail al-Juburi, a senior officer for Nineveh province, killing his son, nephew and sister-in-law -- and wounding 21 others, police said.

It was not immediately clear if Juburi was present at the time of the attack, which took place in the Al-Sharqat area.

Meanwhile, four suicide bombers struck in various parts of northern Iraq on Wednesday which left four people dead.

In other attacks on Saturday, a roadside bomb killed two soldiers and wounded two others in Nineveh province, an army officer said.

And in Tikrit, also north of the capital, gunmen killed Sabhan al-Ajili, the owner of a money exchange shop, according to police.

April was the deadliest month for Iraq in nearly five years, with more than 700 people killed in violent attacks across the country.

A wave of violence began on April 23 when militants invaded security checkpoints near the town of Hawijah in north Iraq, sparking clashes in which 53 people were killed.