Tegucigalpa, Honduras (CNN) -- A group of U.S. lawmakers is calling for a halt in aid to Honduras until the government there makes progress in investigating a rash of journalist deaths in the past two years.
Ninety-four members of Congress signed a letter to Secretary of State Hillary Clinton Monday, proposing a cutoff to all military and police aid until the issue of human rights violations in Honduras are addressed.
Local human rights groups say Honduras will remain one of the deadliest countries for journalists as long as there is impunity for their murderers, pointing to the deaths of 19 journalists since President Porfirio Lobo Sosa took office in January 2010.
The latest calls for action come after the killing of radio host Fausto Valle in northern Honduras this week. His attackers killed him with machetes.
Human rights activists say that the government moves too slowly, and has failed to bring perpetrators to justice for the killings.
"Under this level of impunity, logically the killings will continue if the government does not show resolve a criminal investigation, an investigation that has so many shortcomings that you know it will not determine and will not find the people who committed these killings nor the masterminds behind it," said Wilfredo Mendez, coordinator for the Center for Investigation and Promotion of Human Rights in Honduras.
The groups say the government's lack of results is part of a bigger effort to squeeze media outlets and stifle freedom of the press.
The government denies the accusations.
"The president is absolutely not wanting to restrict the freedom of expression or pass decrees that go against this," said Miguel Angel Bonilla, the minister of communications.
He cited a recent meeting between government officials and representatives from the Inter-American Press Association.
"They have seen that the president's will is to solve these crimes. We have asked for help because we have some problems in the area of investigations in our country."
Bonilla downplayed the call by American lawmakers to restrict financial aid to the Honduran military and police.
"It's an option that those lawmakers have, but it is not an issue that we see as an action by the people and the government of the United States against our country. We are truly working hard, President Lobo has a lot of will to see these issues improve," he said.
According to press freedom groups, a total of 21 journalists have been killed in Honduras since 2003.
By authorities' own count, arrests have been made in only four cases, though the motives behind the killings remain unknown.
Worries continue as many journalists complain of threats in the course of their work, said Hector Becerra of the Committee for Free Expression.
"Already this year we have 20 alerts that that committee put out. These 20 alerts reflect different aggressions, including threats, intimidation, and following journalists," he said.
Valles' brutal slaying this weekend "reflects that in our country, it is definitely risky to practice journalism," he said.