Two radio journalists were shot dead in the Dominican Republic on Tuesday during a live broadcast streaming on Facebook, according to local media reports.

Luís Manuel Medina, a radio presenter at the station 103.5 HICC, and Leo Martinez, a producer and director, were killed in the attack. A secretary, Dayaba Garcia, was injured and had to undergo emergency surgery, according to the Guardian.

The outlet reports three men were arrested in the city of San Pedro de Macorís, about 50 miles from the capital, Santo Domingo. They have not yet been charged.

A video of the incident shows Medina reading the news as what appears to be gunshots ring out in the background. A woman can be heard yelling “Shots! Shots!” before the transmission ends, according to a translation from The Associated Press.

The Committee to Protect Journalists has only documented the murder of three reporters in the Dominican Republic since it began tracking such statistics in 1992. But journalists have faced harassment and death threats in recent years for their work. Four people said they were threatened after writing about an immigration debate in 2015. Government officials opened an investigation into the harassment, but no one was charged.

Olivo de Leon, a professor of journalism in the country, told The Guardian the shooting was “unprecedented,” and called for an investigation into why the men were murdered.

“The authorities must investigate to determine not just the killers but also the intellectual authors so that we know why they were murdered,” de Leon said. “Impunity in this case will generate fear among journalists, making them scared to speak out and do their jobs. The government must guarantee freedom of expression.”