XXXTentacion death: Dedrick Williams arrested on suspicion of first degree murder after rapper is gunned down aged 20

Police have made an arrest in their investigation into the shooting of US rapper XXXTentacion.

The controversial rapper was shot dead aged 20 in south Florida on Monday while leaving a motorcycle dealership.

The rapper, who was facing domestic violence charges, was rushed to hospital where he was pronounced dead.

Florida's Broward County Sheriff's Dept said Dedrick D. Williams, 22, was arrested on suspicion of committing first degree murder.

XXXTentacion's lawyer, David Bogenschutz, said investigators believed the slaying was a random robbery.

Mr Bogenschutz said the rapper might have withdrawn cash to buy a motorcycle.

In Los Angeles, hundreds of fans turned Melrose Avenue into a mosh pit in celebration and mourning of XXXTentacion on Tuesday night.

In an impromptu memorial outside a Hollywood bike shop, fans filled the street and danced on rooftops shouted along with his songs.

A big painted sign in the shop window read RIP XXX followed by hearts.

Police closed off the street and let the party grow to nearly 500 people before calling for the crowd to clear out.

The entertainer, who sported dreadlocks and facial tattoos, was a rising star. He notched a No. 1 album in March with his sophomore effort "?" and had a top 10 hit with "Sad!" but was facing trial on charges that he beat up his pregnant girlfriend.

His brief career was marked by controversy. In 2016, he was arrested on charges including home invasion for a 2015 incident, and less than a month later was jailed on charges that he attacked his girlfriend, who was pregnant at the time. Later, he faced more charges including witness tampering.