Police Sgt. Vince Inaudi said the children appeared to be sleeping when they were shot. The evidence was consistent with a murder-suicide, but the department planned to conduct a full homicide investigation, he said.

Authorities identified the dead siblings as Aubrie, 12; Jacob, 10; and twins Taylor and Alyssa, both 5. The wife, Amanda Branscum, was uninjured, officials said.

The Branscums had lived in Gustine for three years, and there were no reports of domestic violence with the family, Inaudi said. Trevor and Amanda Branscum were married on Valentine's Day in 2003, Inaudi said. All four children were theirs.

Steven Morris, 18, who lived across the street from the Branscums, said he saw the family lighting fireworks on their front lawn Monday night.

"They always seemed really happy," Morris said. "I never heard any arguments from the house. It's sad because the kids didn't do anything. Kids don't deserve that."

The bloodshed came about an hour after a store owner called police to report that Trevor Branscum and his wife were arguing.

Amanda Branscum went in to buy a few things, and her husband followed her into the market, police said. The merchant said that as the woman drove away in a van, her husband dove through the window. The store owner declined to comment on the dispute that preceded the violence.

As officers searched for the van, police said, another call came in at 1:30 a.m. of shots fired at the Branscum home. Officers saw Amanda Branscum lying in the road uninjured; the bodies of Trevor Branscum and the children were inside the house.

Gustine, with a population of about 5,200, is about 90 miles northwest of Fresno in California's San Joaquin Valley. The deaths Tuesday were the community's first reported killings in nearly four decades.

"It's kind of shocking in this area," said 41-year-old neighbor Francisco Torres, whose daughter was friends with Aubrie. "You always hear about crime in other cities, but it's shocking because it's your own neighbors."

Melton, who was out of town on vacation, could not be reached for comment on Sunday.

Lewis said Melton is receiving feedback from beat officers who are talking to people in the community and observing activities and juveniles in the neighborhoods.

After midnight Friday, Jackson saw its second homicide during the state-of-emergency period in a quintuple shooting outside a west Jackson nightclub.

Uriel Castillo, 22, of Pearl was shot and killed outside the Taqueria Mexicana in the Bel Air Shopping Center at 1999 U.S. 80 West. Castillo was shot once in the chest and once in the arm, Hinds County Coroner Sharon Grisham-Stewart said Saturday.

Police would not release the names of the other four men, but described them as all being in their 20s. One was in serious condition with a wound to his back. The other three were released from local hospitals.

JPD Cmdr. Lee Vance said Sunday that police had no other details to release in the shooting, and no arrests have been made.

On June 23, Terry Thomas, 39, of Jackson was shot to death in west Jackson. No arrests have been made in that case.

Some in the Lanier High School area were questioning Sunday what it would take for the mayor, whose campaign was based on crime-fighting, to end the emergency period.

Helen West, 58, who sat on her porch Sunday on Rondo Street with Bobbie Ramsey, 38, said she didn't feel a difference in her neighborhood since the state of emergency began. Her neighborhood remained quiet.

Ramsey, whose eldest child is 14 years old, said she didn't have to worry about her children missing curfew, because they were at home.

"If you have a 14-year-old, you should know where they are at 10 p.m.," she said.

The curfew, though, makes other parents accountable for the whereabouts of their children, she said. "It gives parents more responsibility to know where their children are at that time of night," Ramsey said. "I feel safer that he's (Melton) doing that."

She said it's hard to tell if the curfew is really working in keeping crime down, because the amount of crime being committed is not known. "We won't know if it's making a difference until crime has gone down," Ramsey said.

City officials have said that the number of minors arrested for curfew violations during the emergency period will not be made public until the state of emergency ends.

Geneva Tillman, 72, who was doing yardwork on Campbell Street, said she used to sit out on her porch, but is afraid to because of the crime she hears about in the area.

Although her street is "pretty quiet," she said it doesn't seem like crime is being reduced in the city because of the curfew. "You can't tell," she said. "There are things going on every night." But, Tillman said, the curfew has only been in effect for 10 days, and it's too early to tell if it's working. "We have to give it time," she said.

The extremist Islamic movement, which is waging an insurgency against the government, said it had planted the two cart bombs. It also claimed responsibility for a similar attack on Tuesday that injured four people.

An explosion at 8:00 am struck a bus taking commerce ministry office workers to work in the northern Khair Khana suburb, according to officials and NATO's International Security Assistance Force (ISAF) that patrols the city.

"One person was martyred and four wounded," interior ministry spokesman Yousuf Stanizai said.

About an hour earlier a similar blast struck a bus transporting Afghan National Army (ANA) army officers in a busy southcentral area of Kabul, police said.

"A bomb exploded on the side of the bus in which around 40 officers were wounded, many of them lightly wounded," defence ministry spokesman General Mohammad Zahir Azimi told AFP.

After the blast, the bus veered off the road and slammed into a shop selling gas. The bus was gutted in the blaze, and part of the shop was also destroyed.

"There were explosives in a cart on the road side and while the ANA bus was passing by, the explosion took place," Kabul police criminal investigation director Ali Shah Paktiawal said.

"The bus got out of control and went into a shop," he said.

Purported Taliban spokesman Yousuf Ahmadi said the movement had carried out the blasts.

"It was a remote-controlled bomb," he told AFP. He said the target was a police vehicle and that six people had been killed, a toll which was not confirmed by authorities.

The blast on the army bus took place just a few hundred metres (yards) south of an area near the presidential compound and several government ministries where explosives packed into a wheelbarrow caused an explosion Tuesday that wounded around four people.

That was the second explosion in the city on Tuesday: a policeman was slightly wounded when a remote-controlled bomb hit a police vehicle in eastern Kabul.

Such bomb blasts have been rare in the capital although they occur regularly in other parts of insurgency-hit
Afghanistan.

They are usually blamed on the Taliban, which was removed from power by a US-led coalition and an alliance of Afghan warlords in late 2001.

Around 600 people have been killed since May in a spike in insurgency-linked violence. Most have been militants killed by Afghan and foreign security forces, who are conducting one of their biggest operations in Afghanistan.

Azimi, from the defence ministry, said militants were targeting the city because they had suffered heavy casualties in the south.

"This is the work of the enemies of Afghanistan who sustained heavy losses in the south and by suicide and bomb explosions they want to recompense," he told AFP.