Ben Carson, the secretary of the Department of Housing and Urban Development, said in an interview with the PBS NewsHour on Tuesday that he has not seen evidence that white supremacists groups reflect a growing threat, despite several organizations publicly concluding that the groups have recently multiplied.

The comments by Carson, who is the only black cabinet member in the Trump administration, echo President Donald Trump’s statements last week after the terror attacks in New Zealand. When asked at the White House whether he saw white nationalism as a rising threat around the world, Trump said, “I don’t really. I think it’s a small group of people that have very, very serious problems.”

On Tuesday, Carson was asked whether he agreed with the president’s stance on white supremacists, given that experts have released information showing that the groups are growing and leading to a rise in hate crimes.

“I personally have not seen evidence of it,” Carson said in the NewsHour interview. “But, again, if there is even one, it’s a problem.”

The Anti-Defamation League, a group that tracks white supremacists, released data earlier this month showing that white supremacist groups dramatically stepped up their propaganda efforts targeting neighborhoods and campuses in the United States in 2018. The group found that reports of the propaganda — which can include fliers, stickers, banners and posters that promote hateful ideology — rose 182 percent, to 1,187 cases. That’s up from 421 reported incidents in 2017.

The organization also found that in 2018, domestic extremists killed at least 50 people in the U.S., up from 37 extremist-related murders documented in 2017. The Anti-Defamation League report said the extremist-related murders in 2018 — including the 11 people killed in a shooting at Pittsburgh’s Tree of Life Synagogue — were overwhelmingly linked to right-wing extremists and that “white supremacists were responsible for the great majority of the killings, which is typically the case.”

The Southern Poverty Law Center, which also tracks hate groups, found that more hate groups were operating in the the U.S. last year than in the past 20 years. In 2018, the group documented 1,020 hate groups, and concluded that “President Trump continued to fan the flames of white resentment over immigration and the country’s changing demographics.”

But Carson questioned whether discussing the number of groups mattered. “Well, I don’t know that anything useful comes from talking about what size they are,” he said Tuesday. “They’re a despicable group of individuals, as any group that hates others and purports themselves to be superior.”

Trump has received backlash in recent days from some who claimed he did not condemned white supremacy enough after a gunman in New Zealand killed 50 people by shooting at two mosques last week. White House officials have denied that the president’s rhetoric has been a factor in this kind of violence.

Carson said white supremacists should be universally condemned. “I think we should all, regardless of what our political prospects are, condemn anybody who is a hate group, no matter what their size, whether they’re getting smaller, whether they’re getting larger,” he said.