Texas Rangers are now looking into shootings on Mexico’s side of the Rio Grande.

Authorities at the Thursday DPS Operation Lone Star briefing said groups of people on the Mexican side of the river are taunting and shooting at Texas National Guard soldiers across the border. 

The latest incident occurred last week in Starr County.

WATCH: DPS discusses military surge during Operation Lone Star briefing

“They are heavily armed, they are wearing tactical gear, and we've never seen that before in prior years, and it's becoming more common now," DPS spokesman Lt. Christopher Olivarez said.  "We are providing more resources to those particular areas where there is increased activity along with our partners along with our Texas National Guard, and we have our Texas Rangers doing full investigations on these incidents, and we're working with our federal partners." 

Operation Lone Star authorities have also seen more illegal activity in Cameron County over the past several weeks.

In an effort to keep enough personnel patrolling the river and across the Valley - the Texas National Guard will be sending more soldiers to the southwest border to help with Operation Lone Star.