Two alleged members of the Gulf Cartel are behind bars following a traffic stop south of the border in Valle Hermoso.
It all happened off Calle Hidalgo on Monday.
The Mexican Navy (SEMAR) reported that marines were patrolling the area when they stopped a car with two men inside.
Marines allegedly found weapons, ammunition and grenades inside.
Authorities also found $15,000 pesos and $500 dollars as well as uniforms and clothes with Gulf Cartel logos and nicknames.
The names of the two men were not released but Mexican Navy officials report that they remain in custody and face criminal prosecution.
Valle Hermoso has been a battleground between former allies the Gulf Cartel and the Zetas drug cartel since February 2010.