The US Border Patrol was involved in a shooting in Arizona on Tuesday, Pima County Sheriff Chris Nanos said in a statement, adding that his office was working with the FBI and Customs and Border Protection to look into the incident.

NBC News earlier reported, citing a Pima County Sheriff spokeswoman, that a person was in critical condition after being shot in an incident involving the Border Patrol.

The circumstances of the incident were not immediately clear and the person who was shot has not been identified. The Department of Homeland Security did not immediately respond to a request for comment.

Arivaca, the community about 10 miles (16 km) from the US-Mexico border where Nanos said the incident took place, is a busy crossing area for migrants and is also the site of past tension between migrant advocates and Border Patrol.

The incident comes after the killing of 37-year-old Alex Pretti, an ICU nurse shot multiple times by federal immigration agents on Saturday in Minnesota.

Coupled with the fatal shooting of Renee Good, also 37, earlier this month by an Immigration and Customs Enforcement officer, Pretti’s shooting has become a major political headache for President Donald Trump and sparked renewed anger over the aggressive tactics of the federal agents who have been roving the streets of Minneapolis for weeks.

Trump won the 2024 presidential election after promising a historic surge in deportations and has pursued a hardline immigration agenda since taking office last year.

Masked immigration officers, often in tactical military-style gear, have become a common sight across the country and protests against the crackdown have erupted in several cities, including Minneapolis, where immigration agents have responded with deadly force.

Public support for Trump’s immigration enforcement tactics appeared to be waning both before and after the Pretti shooting, a recent poll showed. The issue has put Republicans on the defensive ahead of November’s midterm elections, when the party’s narrow congressional majorities are at stake.