MEXICO CITY (AP) — More than 1,000 Mexican journalists marched through the city center Saturday to protest the killing and disappearance of their colleagues as escalating drug violence increasingly targets reporters.

Carrying signs reading "Not one more!", they demanded protection to do their work in an unprecedented effort to solidify the ranks of a traditionally divided and competitive profession.

"We're a little late — 64 killings late — but we've finally decided to practice our right to protest, to seek justice for our colleagues who have died or disappeared and to end the impunity for crimes against journalists," said Elia Baltazar, protest organizer and co-editor of the Mexican newspaper Excelsior.

International media groups call Mexico one of the most dangerous countries for practicing journalism.

Similar demonstrations were planned in states hardest hit by drug violence, including Sinaloa, home to a powerful cartel of the same name, and Chihuahua, home to Ciudad Juarez, Mexico's most violent city.

Participants hoped to open talks with Mexican authorities on security protocols for journalists, some of whom have stopped reporting on drug violence in fear of their lives.

"We should think about how we can guarantee the delivery of information to the public," Baltazar said. "We're very concerned about the pattern of silence."

More than 60 journalists have died as a result of their work since 2000, according to the National Human Rights Commission, and many others suffer harassment and threats from drug lords.

The killings have increased this year, though organizations report different numbers. The human rights commission says seven journalists have been slain so far this year, while Reporters Without Borders puts the number at 10.

Local journalists in Mexico have long been under siege from drug traffickers. But the recent kidnapping of four journalists, three of them with national television networks, signaled a new level of attacks on reporters. Two were let go by their captors and police rescued the other two.