MCALLEN, Texas — Border Patrol agents seized more than $650,000 in cash that had been left behind near the Rio Grande River that separates Texas from Mexico.

The seizure was made Thursday night when U.S. Border Patrol Agents following a set of footprints near Sullivan City ended up coming across four backpacks filled with bulk cash and a little more than a kilo of cocaine, an agency news release shows.

Inside the four backpacks the agents ended up finding a mixture of dollars and pesos that added up to $650,000 as well as the cocaine which had a value of $90,000.

Just west of Sullivan City, in Rio Grande City, border patrol agents seized 20 rounds of .50 caliber ammunition, 1o of the rounds were incendiary, five armor piercing and five regular rounds, the news release shows.

Drug smugglers having heavy firepower is typically seen in Mexico, however in recent years federal, state and local authorities have been coming across drug traffickers with grenades and assault weapons.

Earlier this week, narcotics investigators with the Hidalgo County Sheriff’s Office seized a weapons cache which included a grenade while conducting a drug raid, sheriff’s investigators told Breitbart Texas. During the raid at an Alton stash house, investigators seized 19 firearms, a grenades, 56 pounds of marijuana and 18.5 pounds of meth, court records show. Investigators also arrested three men who are now facing state drug trafficking charges.

Follow Ildefonso Ortiz on Twitter: @ildefonsoortiz