A longtime Republican Party donor based in Florida vowed not to contribute any more money to candidates or electioneering groups until they pass legislation banning the sale of assault weapons to civilians.

Al Hoffman Jr., a real estate developer and former ambassador to Portugal, has donated millions to Republicans over the years. On Saturday he sent an email to a half-dozen Republican donors, encouraging them to boycott candidates who oppose new gun legislation, the New York Times reported.

“For how many years now have we been doing this — having these experiences of terrorism, mass killings — and how many years has it been that nothing’s been done?” Hoffman said. “It’s the end of the road for me.”

Hoffman warned that unless the government intervenes, more gun massacres are going to occur.

“If we go from Orlando to Las Vegas, and now Parkland, you just have to know that there are others around the country just dreaming about staging another mass murder,” he said.

Peter S. Rummell, another Florida-based GOP donor, said he was on board with Hoffman’s plan and would only support candidates who were in favor of banning assault weapons.

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