Four Detroit men were arrested for threatening on Facebook to kill white police officers, police chief James Craig said Sunday.

One of the men is accused of posting “All lives can’t matter until black lives matter. Kill all white cops,” The Detroit News reported.

The post comes just days after five police officers were killed and nine others injured during a rampage and standoff in downtown Dallas.

Craig said he was taking social media threats seriously in the aftermath of the attack.

“Social media is new territory, and while it’s been established that hate speech is protected by the First Amendment, we’re talking about people specifically saying on Facebook they want to kill white police officers,” Craig said.

“If someone threatens to kill the president, that person would be arrested and prosecuted. How is it any different when someone threatens to kill white cops?”