KABUL (Reuters) - The Afghan policewoman suspected of killing a U.S. contractor at police headquarters in Kabul suffered from mental illness and was driven to suicidal despair by poverty, her children told Reuters on Wednesday.

Fatima, 13, holds a picture of her mother Narges Rezaeimomenabad, suspected of killing a U.S. contractor at a police headquarters, at her home in Kabul December 26, 2012. REUTERS/Mohammad Ismail

The woman was identified by authorities as Narges Rezaeimomenabad, a 40-year-old grandmother and mother of three who moved here from Iran 10 years ago and married an Afghan man.

On Monday morning, she loaded a pistol in a bathroom at the police compound, hid it in her long scarf and shot an American police trainer, apparently becoming the first Afghan woman to carry out such an attack.

Narges also tried to shoot police officials after killing the American. Luckily for them, her pistol jammed. Her husband is also under investigation.

Her son Sayed, 16, and daughter Fatima, 13, described how they tried to call their parents 100 times after news broke of the shooting, then waited in vain for them to come home.

They recalled Narges’s severe mood swings, and how at times she beat them and even pulled out a knife. But the children said she was consistent in bemoaning poverty.

“She was usually complaining about poverty. She was complaining to my father about our conditions. She was saying that my father was poor,” Sayid said in an interview in their damp, cold two-room cement house.

On the floor beside him were his mother’s prescriptions and a thick plastic bag filled with pills she tried to swallow to end the misery about a month ago. On another occasion, she cut her wrist with a razor, Sayed said.

“My father was usually calm and sometimes would say that she was guilty too because it wasn’t a forced marriage. They fell in love and got married.”

There was no sign in their neighborhood of the billions of dollars of Western aid that have poured into Afghanistan since the ouster of the Taliban in 2001, or of government investment.

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RAW SEWAGE, STAGNANT WATER, DIRT ROADS

The lane outside their home stank of raw sewage.

Dirty, stagnant water filled holes in dirt roads nearby, where children in tattered clothes played and butchers stood by cow’s hooves in shops choked by dust.

Afghanistan is one of the world’s poorest nations, with a third of its 30 million residents living under the poverty line.

The sole distractions from the daily grind appeared to be a deck of playing cards and a compact disc with songs from Iranian pop singers, scattered on the floor of a room where Narges would lock herself in and weep, or sit in silence.

At times, Narges would try to focus on building her children’s confidence, telling them to be guided by the Muslim holy book, the Koran, to tackle life’s problems.

Sayed and Fatima said she never spoke badly of the U.S. presence in Afghanistan or of President Hamid Karzai’s government.

Neighbor Mohammad Ismail Kohistani was dumbfounded to hear on the radio that Afghan officials were combing Narges’ phone records to try to determine whether al Qaeda or the Taliban could have brainwashed her into carrying out a mission.

But he was acutely aware of her mental problems and often heard her scream at her husband, whose low-level job in the crime investigation unit of the police brought home little cash.

Kohistani, who operates a small sewing shop with battered machines, never imagined his neighbor could be accused of a high-profile attack that raised new questions about the direction of an unpopular war.

“I became very depressed and sad,” said Kohistani, sitting on the floor few feet from a tiny wood-burning stove in Narges’s home, alongside family photographs and a police training manual.

Fatima would often seek refuge in Kohistani’s house when her mother’s behavior became unbearable. “She did not hate us, but usually she was angry and would not talk to us,” said Fatima, her eyes moist with tears.

Nevertheless, she missed her mother. The children were staying with a cousin.

“I ask the government to free my mother, otherwise our future will be destroyed,” said Fatima.

Officials described it as another “insider shooting”, in which Afghan forces turn on Westerners they are meant to be working with to stabilize the country. There have been over 52 such attacks so far this year.

The shooting at the police headquarters may have alarmed Afghanistan’s Western allies. But some Afghans have grown numb to the violence.

Kohistani’s 70-year-old father Omara Khan, who sports a white beard, sat twirling prayer beads beneath a photograph of Narges in a black veil beside one of her husband.

Asked what he thought of the attack, he laughed.

“This is common in Afghanistan,” said Khan, who lived through decades of upheaval, including the 10-year Soviet occupation and a civil war that destroyed half of Kabul and killed some 50,000 civilians.

“People are killed every day.”