Oscar-winning director Alejandro González Iñárritu and actor Diego Luna joined dozens of other Hispanic cultural leaders in signing a letter on Tuesday criticizing Republican presidential candidate Donald Trump for “hate speech” that they claim is encouraging “physical aggressions against Hispanics.”

“We refuse to keep silent in the face of the alarming declarations of the candidate for the presidency of the United States Donald Trump,” the Spanish-language letter published on Univision reads, according to a translation from Time.

The letter continues:

His hate speech appeals to lower passions like xenophobia, machismo, political intolerance and religious dogmatism. All of which inevitably reminds us of the past campaigns that have been directed against other ethnic groups and that have resulted in the deaths of millions of people. In fact, the physical aggressions against Hispanics and repeated calls to prohibit the public use of the Spanish language have already started.

Other signatures on the letter include those of author Junot Diaz and former Mexican ambassador to the U.S. Arturo Sarukhan. In all, 50 Hispanic cultural leaders signed their names to the letter.

The publication of the letter came the same day that Rep. Loretta Sanchez (D-CA), a member of the Congressional Hispanic Caucus, said that Trump’s campaign was threatening the safety of Latinos. Hispanic lawmakers recently approved a “Statement of Opposition” to protest NBC’s decision to have Trump host this weekend’s episode of Saturday Night Live.

“It is enabling him after he’s said these derogatory comments,” Sanchez said of the decision to allow Trump to host the late-night variety program. “And NBCUniversal said to us early on, ‘We’re not going to stand for this.’ So we are simply pushing back at SNL and saying, ‘Uh uh, this is not correct, and you are endangering Latinos when you do this type of of a thing.’”

Other advocacy groups, including the National Hispanic Media Coalition and the National Hispanic Leadership Agenda, have similarly protested Trump’s hosting of Saturday Night Live. NBC has not responded to the pressure.

The first teaser for Donald Trump’s Saturday Night Live episode was released Wednesday.