Former Republican presidential candidate Marco Rubio says tougher gun control in the US would not have prevented the mass shooting at a gay nightclub in Orlando.

Speaking to the BBC's Jon Sopel, the Senator for Florida said there should be less focus on the weapons used in the attack, and more attention paid to the motivations behind it.

He said home-grown terrorism was the hardest challenge the US faced.

The gunman who killed at least 50 people at the Pulse nightclub in Florida has been named as Omar Mateen, a US citizen first questioned over alleged links to extremism by the FBI in 2013.