Two suicide bombers killed a senior Iraqi intelligence officer and two guards near the main northern city of Mosul on Saturday, while other blasts left two more people dead, officials said.
The attacks were the latest in a surge in violence that comes as Iraq grapples with nearly two months of anti-government protests and a political crisis.
Brigadier General Aouni Ali, who headed the country's main intelligence academy, and two of his guards were killed outside the officer's home in Tal Afar near Mosul, police and a doctor said.
A colonel in the Tal Afar police said the attack involved two suicide bombers -- one who killed two guards and wounded four others, and a second who killed the general himself.
Lower-ranking officers and enlisted personnel are usually the victims of attacks on Iraqi security forces, but senior officers including generals are periodically targeted and killed as well.
Also north of Baghdad, a judge was killed by a magnetic "sticky bomb" attached to his car in the village of Sulaiman Pak, according to security and medical officials.
Ahmed al-Bayati, a Sunni Arab who is now a judge handling civil cases, had previously received threats while he was working as an anti-terror investigator, and had to pay kidnappers a $150,000 ransom after his son was snatched last year.
Elsewhere, a roadside bomb killed an army lieutenant and wounded two soldiers in Heet, northwest of the capital.
No group claimed responsibility for the blasts, but Sunni militants linked to Al-Qaeda often target security forces and government officials in a bid to erode confidence in the government and push Iraq back towards the bloody sectarian conflict that plagued the country in past years.
Iraq has seen a rise in attacks in recent weeks. The latest violence brings the number of people killed in the country this month to 135, according to an AFP tally based on security and medical sources.
However, levels of violence remain markedly lower than during the peak of the sectarian war in 2006 and 2007.