Three mobile billboards appeared in front of Republican Senator Marco Rubio's headquarters in Miami on Friday in response to Wednesday's mass shooting in a Parkland, FL, school.

The demonstration mimicked the Oscar-nominated film, Three Billboards Outside Ebbing, Missouri, in which a grieving mother takes aim at the town's police chief with rented ads for the unresolved murder of her daughter.

The signs challenging the former 2016 presidential candidate read: "Slaughtered in school," "And still no gun control?," "How come, Marco Rubio?"

The campaign was started by Avaaz, an online activist group that describes itself as a "global web movement to bring people-powered politics to decision-making everywhere."

The group's deputy director, Emma Ruby-Sachs, explained the motive for publicly calling out the Senator:

Florida has notoriously lax gun laws, and Rubio, who is supported by the NRA, has never attempted to reform them. The senator ranks as one of the highest recipients of NRA contributions and has received an A+ rating from the NRA.

After 19-year-old Nikolas Cruz opened fire at Marjory Stoneman Douglas High School by using a legally purchased AR-15-style rifle and killed at least 17 people, Rubio stated at a Thursday press conference that gun restrictions would not have prevented the mass shooting.

I understand. I really do. You read in the newspaper that they used a certain kind of gun and therefore let's make it harder to get those kinds of guns. I don't have some sort of de facto religious objection to that or some ideological commitment to that, per se.

If we do something, it should be something that works. And the struggle up to this point has been that most of the proposals that have been offered would not have prevented, not just yesterday's tragedy, but any of those in recent history. Just because these proposals would not have prevented these does not mean that we therefore raise our hands and say, 'Therefore, there's nothing we can do.

Rubio is supported by the NRA and has received $3.3 million from them since October 2017, according to the New York Times.

If the Three Billboards film fails to nab an Oscar, at least it inspired a legacy.

H/T - Twitter, NYtimes, CNN, CNN2, NBC