Madonna has urged her fans to "wake up" and demand gun control in the US.
The Queen of Pop, 60, has previously criticised President Donald Trump for failing to act on the issue.
In a social media post, the veteran singer asked her 2.5 million followers to "honour the victims" of gun violence.
On Twitter, she wrote: "This is your wake up call. Gun violence disproportionately affects children, teenagers and the marginalized in our communities.
"Honor the victims and demand GUN CONTROL. NOW. Volunteer, stand up, donate, reach out."
In a second tweet, she said: "Wake up and insist on common-sense gun safety legislation. Innocent lives depend on it."
She also urged her fans to follow a number of organisations including Sandy Hook Promise, which trains students to recognise signs of gun violence, and the US advocacy group National Centre for Transgender Equality.
The message came as she unveiled the graphic video for her single God Control, which depicts a shooting at a fictional disco club called the Globe.
The eight-minute video may be in reference to the 2016 mass shooting at the gay nightclub Pulse in Orlando.
The video begins with a message which reads: "The video you are about to see is very disturbing. It shows graphic scenes of gun violence.
"But it's happening every day. And it has to stop."
