Nadhim al-Juburi weeps in a funeral tent in central Baghdad, mourning two sons killed in a bombing days before the sixth anniversary of a third son's death in another blast.

Juburi, 56, briefly stops crying and says in a shaky voice: "The children are dead! Alaa! Abbas! Ali! Now I have three martyrs!"

Tears roll down his face again.

Ammar, 17, stands near his father, accepting condolences for the death of his two brothers. He is now his father's only living son.

Police search mourners as they arrive at the tent, seeking to prevent another deadly blast.

A message on a black banner near the tent says that Alaa, 24, and Abbas, 18, were killed in a "cowardly terrorist explosion."

The two brothers were victims of a car bomb that detonated on Saturday evening near the cart where they sold watermelons, in the Karrada district of central Baghdad.

The blast was part of a wave of attacks in Baghdad province that killed 67 people and wounded almost 200.

More than 600 people have died in violence so far this month -- mothers, fathers, sons, daughters, brothers, sisters, relatives and friends -- each one a loss that causes family and friends wrenching pain.

The Iraqi government has failed to curb the raging violence, the worst to hit the country since 2008.

Alaa and Abbas were killed just days ahead of the sixth anniversary of their brother Ali's death on July 23, 2007.

"In 2007, a car bomb in the same place took Ali as well," just a week before he was to be married, Juburi says.

Alaa had three sons and a newborn daughter, while Abbas was to be engaged after the end of the Muslim fasting month of Ramadan, adds the shattered father.

"I have Ammar left," he says, looking around for his youngest son.

"Ammar! Where is Ammar?" he shouts, and the young man comes running back.

The effects of the blast are still visible, with two men working to restore the porch of a house while another uses a tractor to remove damaged telephone wires from the street.

A heavy scent of spices wafts from a cart smashed by the explosion. Pieces of shoes lay under the cart, and the road is stained with blood.

Near the banner announcing the deaths of Alaa and Abbas, another, faded by years in the sun, bears Ali's picture and the words: "The happy martyr."

"I have never forgotten Ali," his father says, adding that he and his wife sleep near their son's grave in Najaf, south of Baghdad, for several nights each year.

"If I wasn't concerned about my other children, I would have built a small house next to his grave and stayed there."

Juburi recalls how he rushed outside his home when he heard the blast on Saturday, and saw Alaa lying on the ground.

"Go after Abbas," his son said.

The white-bearded father struggled to lift Alaa but eventually succeeded, taking him to the hospital, where he died.

Abbas died at the scene of the bombing.

"Their dishdashas are still with me in the house, with the blood of my sons on them," he says of the traditional robes they were wearing.

Ammar, sitting in a white plastic chair near a picture of his three brothers, says that they were inseparable -- they ate together, talked together, prayed together and slept at the same time.

Now, "I am alone," says Ammar.

"I almost do not believe this; it must be a bad dream."

His father interrupts him and says: "If these people were not here next to me, I would have died from the pain."

"I feel so much pain, I may die anyway. We all came from God and to Him we return. Everything is in the hands of God."