A video journalist is in a coma after becoming injured at a protest in Rio de Janeiro where he was hit with an explosive device.

Ilídio Andrade, cameraman for the television network Bandeirantes was filming a clash between police officers and demonstrators who were protesting increases in public transportation fares.

The device hit him in the head, and exploded on contact. He lost a piece of his ear, and had to undergo surgery immediately, Brazilian news reports said.

The Committee to Protect Journalists has called for an investigation into Andrade’s injury due to conflicting reports on who was responsible.

Police officials said protesters threw the device, but another television journalist who was on the scene told the Rio de Janeiro-based G1 television network he saw police do it.

Carlos Lauria, CPJ’s senior program coordinator for the Americas said authorities need to help facilitate safer news coverage. “In the months leading up to the World Cup, Brazilian authorities must learn from last year’s mistakes–when dozens of journalists were injured or arrested while covering protests–and ensure that journalists can safely cover demonstrations,” he said.

Last year, police and protestors targeted dozens of Brazilian journalists covering anti-government protests because they didn’t like their networks’ coverage. At least three journalists were arrested and more than 25 reported being violently attacked.