At least 50 people have been killed and more than 200 injured after a gunman opened fire at an open air concert in Las Vegas.

It is believed to be the deadliest mass shooting in modern US history and the death toll is expected to rise.

Here are some of the worst mass shootings in America since 1949:

In June 2016, 49 people were killed after lone gunman Omar Mateen opened fire in a gay club in Orlando, Florida.

Fifty-eight people were also injured.

So-called Islamic State claimed responsibility for the attack but investigators found no clear evidence Mateen was directed by the terror group.

On April 16, 2007, student Seung Hui Choi, killed 32 people and wounded 17 others before killing himself on the campus of Virginia Polytechnic Institute and State University in Blacksburg, Virginia.

The murder of 26 people, including 20 children, at an elementary school in Newtown, Connecticut, in December 2012, sent shock-waves across America and beyond.

Then US President Barack Obama was unable to hold back tears as he spoke about the youngest victims of the Sandy Hook shootings while speaking about measures to reduce gun violence.

In 1991, 23 people were killed after George Hennard opened fire at a cafe in Killen, Texas. Twenty-seven people were also injured.

In 1984, 21 people were killed in an McDonalds in San Ysidro, California by an out-of work security guard called James Huberty. He was later killed by police.

In December 2015, 14 people were killed when Syed Rizwan Farook and Tashfeen Malik opened fire at an office party in San Bernardino, California.

The married couple were said to have been radicalised "for quite some time" before the deadly attack.

On April 20, 1999, 18-year-old Eric Harris and Dylan Klebold opened fire at Columbine High School in Colorado, killing 12 classmates and a policeman before committing suicide.

Twenty-four other people were injured,

The shooting led to a renewed focus on gun violence and prompted Michael Moore's Oscar-winning documentary Bowling for Columbine.

In 1986, 14 people people were shot by Pat Sherrill inside a post office in Edmond, Oklahoma.

At least 12 people were killed when James Holmes entered cinema in Aurora, Colorado, released a canister of gas and opened fire during the opening night of the Batman movie The Dark Knight Rises in 2012.

Holmes pleaded not guilty by reason of insanity but was convicted of murder in 2015 and sentenced to life in prison.

The trend of deadly shooting sprees in the United States stretches back decades.

In 1966, Sixteen people were killed and more than 30 were wounded during a 96-minute rifle rampage by student Charles Whitman at the University of Texas in Austin.

Ten years later in 1976, seven people were killed in the library of California State University, Fullerton.