Three U.S. lawmakers are calling for stricter gun laws, in response to a report saying Mexican drug gangs are getting their firepower from the United States.
The report, prepared for the Senate Caucus on International Narcotics Control, says 70 percent of the guns recovered at crime scenes in Mexico and traced by authorities came from the U.S.
The chair of the caucus, Democratic Senator Dianne Feinstein, is calling on Congress to act on the findings and stop powerful Mexican drug traffickers from having what she calls "unfettered access" to military-style weapons from the United States.
Two other senators who helped prepare the report have joined Feinstein in calling for tougher gun laws.
The report recommends lawmakers close a loophole that allows private gun dealers to sell weapons at gun shows without conducting a background check on buyers.
It also calls for lawmakers to reinstate a ban on assault weapons that expired in 2004 and says the U.S. must do a better job of enforcing an existing ban on imports of military-style weapons.
The report based its findings on information from the U.S. agency in charge of monitoring and tracking the use of firearms.
Mexico has been increasingly critical of U.S. efforts to stop guns from crossing the border.
Mexican President Felipe Calderon has deployed nearly 50,000 troops in the crackdown against drug violence since he took office in 2006.
More than 37,000 people have been killed in the country's drug war in that time.
Some information for this report was provided by AP, AFP and Reuters.