Six men wearing vests with the initials of a notorious drug cartel in Mexico were found dead near the city of Reynosa, officials in the northern Mexico border state of Tamaulipas said on Wednesday.

An official familiar on the matter said all six men had been shot in the head and were found wearing military-style vests with the initials "CDG," which stands for Cartel del Golfo, according to a U.S. News report.

The bodies were found at a ranch on the outskirts of Reynosa, which is near the Rio Grande. In Mexico, the Rio Grande is known as the Rio Bravo. Authorities said no weapons or any identification were found on the bodies.

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Fight Against Drug Trafficking and Drug Cartel Operations

A top White House official told Mexican officials that the key to the two countries' fight against drug trafficking is not working, and the U.S. is open to pursuing new strategies together, people familiar with the message said.

Senior director for the Western Hemisphere on the National Security Council, Juan Gonzales, made the comments last week on a call between Mexico Foreign Affairs Minister Marcelo Ebrard and U.S. Secretary of State Antony Blinken.

According to a Bloomberg report, people who spoke about the matter asked not to be identified as the conversation was private.

Mexico has long argued that other aspects of the fight against drug trafficking need to be addressed, including the discussion of gun smuggling from the U.S. 

Mexico claimed that gun smuggling fuels the deadly organized crime groups. Gonzales said that Mexico could suggest that they either change or replace the Merida Initiative, which is an agreement signed in 2008. The U.S. has already handed Mexico billions of dollars in security aid as part of the agreement.

The U.S. National Security Council's (NSC) press office said that strategies must evolve just as criminal groups have evolved and that they should be willing to evaluate their own approach objectively.

NSC added that the Merida Initiative elements as originally designed might not be as effective for the challenges today.

"We should be doing more to target money laundering, pre-cursor chemicals, the role of China in fentanyl trafficking through Mexico, as well as investing in economic opportunity and crime prevention," NSC said in the report.

Bloomberg said the U.S. State Department has refused to comment, while Mexico's foreign ministry did not immediately reply to its request for comment.

The Mexico-U.S. Meeting

President Joe Biden and Mexico's President Andrés Manuel López Obrador had a meeting earlier this week, discussing proposals on a temporary worker program and helping Mexico obtain more vaccine.

López Obrador said the meeting was friendly and respectful, adding that there is a lot of emphasis on cooperation for development, according to an ABC News report.

White House officials noted that the Biden administration is focusing on vaccinating U.S. citizens before turning its attention to help other nations secure COVID-19 vaccines.

López Obrador said that there were no differences during his discussion with Biden.

The two leaders also talked about immigration plans, floating the idea that a scale of 600,000 to 800,000 Mexican and Central American workers would be allowed to migrate legally for work.

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