Texas

The male driver was in custody, Lieutenant Martin Sandoval of the Brownsville Police Department said, adding he was charged with reckless driving and could face additional charges.

The incident happened in the city of Brownsville near the Mexican border at about 8.30am local time on Sunday.

Sandoval said the victims in the morning crash were waiting at a bus stop near Ozanam Center, a shelter for the homeless used by migrants. He said some migrants were among the dead.

A San Antonio Fire Department official said they found "stacks of bodies" and no signs of water in the truck, which was found next to railroad tracks in a remote area on the city's southern outskirts.

Sixteen other people found inside the trailer were transported to hospitals for heat stroke and exhaustion, including four minors, but no children were among the dead, the department said.

Officers reportedly delayed confronting the gunman despite knowing children were wounded inside a classroom.

School district police chief Pete Arredondo claimed that officers risked their lives without hesitation.

Nineteen children and two adults were killed in the 24 May shooting at Robb Elementary.

The police response has come under increasing scrutiny in the weeks since the shooting, in which the gunman was locked in two adjoining classrooms with students for more than an hour before police stormed in and killed the attacker.

Public anger is growing after it emerged that officers waited in the hallway as children trapped with the shooter made desperate 911 calls.

US President Joe Biden is in Uvalde to meet families devastated by the attack.

He will also meet survivors and first responders.

First Lady Jill Biden, herself a teacher, accompanied the president to a memorial at Robb Elementary School. They were seen comforting the school's principal Mandy Gutierrez, beside a carpet of floral tributes for the teachers, and children - all under 10 years old - who lost their lives.

At least two children placed several emergency calls from a pair of adjoining fourth-grade classrooms after 18-year-old Salvador Ramos entered on Tuesday with an AR-15 semi-automatic rifle, according to Colonel Steven McCraw, director of the Texas Department of Public Safety.

Ramos, who had driven to Robb Elementary School from his home after shooting and wounding his grandmother there, went on to kill 19 children and two teachers in the deadliest US school shooting in nearly a decade.

The videos emerging - along with initial accounts of the shooting timeline from authorities - suggest up to an hour passed between the time the attack began and the moment specially trained officers breached the fourth-grade classroom where 18-year-old Salvador Ramos had killed 19 children and two teachers, shooting him dead.

The New York Times reported that most, if not all, of the victims of the worst school shooting in nearly a decade likely died in the first few minutes of the attack, citing a person familiar with a preliminary timeline compiled by investigators.

During the shooting on Tuesday, police circled Robb Elementary School in Uvalde, Texas, breaking windows in an effort to evacuate children and staff, Texas Department of Public Safety spokesperson Chris Olivarez told CNN.

Officers eventually breached the classroom and killed the gunman, identified as 18-year-old Salvador Ramos.

Ramos began his rampage by shooting his grandmother at the home where he lived with his grandparents. He then drove to the nearby school where he crashed his car and entered the building wearing tactical gear and carrying a rifle, authorities said.

The 18-year-old gunman carried out the killings at Robb Elementary School in the city of Uvalde.

State Senator Roland Gutierrez who has also released the higher death toll said he was briefed by state police on the fatalities.

The teen is also suspected of killing his grandmother before unleashing the school shooting rampage, three law enforcement sources confirmed to CBS News, the BBC's US partner.

The children attending the school are aged between seven and 10 years.

It is not known if he is armed or if anyone has been hurt.

The service was being streamed live when the incident started. The feed has since been taken down, but not before an angry man could be heard saying he did not want anyone to be hurt.

Police deployed special weapons teams and local people were evacuated.

At least four hostages - including the rabbi - are believed to be inside the synagogue, two law enforcement officials told The Associated Press on condition of anonymity.

The scientists found that heating in the region ultimately disturbed the circular pattern of winds known as the polar vortex.

This allowed colder winter weather to flow down to the US, notably in the Texas cold wave in February.

The authors say that warming will see more cold winters in some locations.

Over the past four decades, satellite records have shown how increasing global temperatures have had a profound effect on the Arctic.

Scientists have long been concerned about the implications of this amplification of global change for the rest of the planet.