An Iraqi official Wednesday defended the performance of his country's security forces after suicide bombers killed more than 60 people in the Baghdad area this week, saying such attacks are nearly impossible to prevent.

Suicide bombers struck Sunday near the police academy, killing 30 people, and again Tuesday at an outdoor market in the Baghdad suburb of Abu Ghraib, where 33 died.

Maj. Gen. Abdul-Karim Khalaf said the spike in attacks should not be considered a breach of security because "no vital target" — such as power stations and government buildings — "has been hit in months."

"Nobody can stop a suicide operation because the suicide bomber explodes himself among crowds of civilians before he reaches a security checkpoint," Khalaf told reporters.

"No security apparatus in the world can protect all the civilians in the streets, and the terrorists consider these civilians in the streets or in their houses as targets," he added.

Khalaf said security forces would intensify intelligence operations to track down militants before they can strike.

He also said Tuesday's suicide bomber, who attacked Sunni and Shiite tribal sheiks touring the market after a reconciliation meeting, had been wearing an Iraqi army uniform.

It was unclear if he was a soldier because such uniforms are available in markets.

No major attacks were reported in the Baghdad area Wednesday.

However, three Iraqi soldiers were killed and up to 14 people were wounded in two separate explosions in the northern city of Mosul.

The three soldiers were killed by a car bomb in western Mosul, the U.S. military said. Two soldiers and 11 civilians were wounded.

In the second explosion, an unknown gunman threw a grenade at a police patrol in central Mosul, wounding two policemen and one civilian, an Iraqi security official said. He spoke on condition of anonymity because he was not supposed to release the information.

A car bomb also exploded as a police patrol passed in the northern city of Kirkuk, killing two civilians and wounding four children, police spokesman Brig. Gen. Sarhat Qadir said.