CHICAGO : A Texas man shot and killed four of his children and two adults looking after them before surrendering to police after a standoff during which he held a gun to his head, officials said.

A fifth child, a 15-year-old girl, was also shot and was in critical condition after the Houston-area shooting Wednesday evening, said Sgt. Thomas Gilliland of the Harris County Sheriff’s Office.

The reason for the latest chapter in the epidemic of gun violence plaguing the United States was not immediately known, but police suspect family troubles led to the bloodshed.  All four of the children were either biological or adopted children of the suspect, Gilliland told reporters at the scene.

The man was separated from his wife, who lived out of state, authorities said, according to CNN. US media showed a photo a heavy-set blond man with his arms raised in the air after he got out of his car in suburban Houston as the standoff ended.

ABC News said the slain children were boys aged 13 and 4 and two girls aged 9 and 7.

The shooting happened in Spring, outside Houston.

One of the children died after arriving at hospital. The two slain adults were men, Harris County Constable Ron Hickman told AFP earlier while the standoff was underway.

Before being taken to hospital, the 15-year-old girl was able to tell authorities where the suspect was headed, triggering a police chase.

She said her father intended to kill her grandparents at another home.

During the standoff the shooter sat in his vehicle surrounded by about 50 police with their guns drawn. There were at least a dozen patrol cars waiting to pounce.

No one was immediately available at the county sheriff’s press office early Thursday.

It was “obviously a domestic situation that went south,” Hickman told a news conference Wednesday evening in Texas. “Probably a divorce or at least a separation.”

The shooting was the latest in a spate of similar incidents in a country plagued by gun violence.

President Barack Obama has warned that America needs to do some “soul-searching” on gun control, which remains relatively lax despite regular gun rampages.

On May 23, a student with mental problems killed six people and then himself in California, while on June 5 a gunman killed one person and injured two others on a campus in Seattle.

In June, a couple with possible anti-government militia links shot dead two police and a civilian in Las Vegas, and a teenage gunman shot a 14-year-old student dead at an Oregon high school.