NEW YORK (CBSNewYork) – City officials want U.S. Immigration and Customs Enforcement to explain how a man ended up getting shot in the face while agents were serving a warrant Thursday morning in Brooklyn.

Law enforcement sources told CBS2 the wounded man was not the subject of their warrant.

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State lawmakers sent a letter to ICE asking to be briefed on what happened and urging the agency to assure the men involved have access to legal counsel.

Shortly before 8:15 a.m., the ICE agent visited a home on West 12th Street between Quentin Road and Highlawn Avenue in Gravesend.

The agency said he was attempting to arrest Gasper Avendano-Hernandez, “a twice-removed illegal alien from Mexico with a 2011 assault conviction in New York City.” The warrant allegedly involved a court appearance for an issue with his car.

Avendano-Hernandez apparently lived at the home with his girlfriend and her two adult sons.

(Credit: Kevin Yanez Cruz)

Law enforcement sources said he briefly barricaded himself inside, while one of the sons – 26-year-old Erick Diaz – confronted the agent just outside the entryway.

A struggled ensued, and the agent discharged his weapon, shooting Diaz once in the face and hand.

The second son, Kevin Yanez Cruz, was inside and came out to see what was going on.

“They didn’t even explain the issue. They just grabbed him like an animal and threw him on the floor,” he said. “He didn’t know what was going on, they didn’t give him no identification, nothing. They didn’t even show him the warrant.”

Diaz was rushed to Maimonides Hospital in serious condition but was expected to survive.

“They shot him straight for the kill,” Cruz added. “They pointed the gun at my brother’s head and shot him in the cheek.”

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Avendano-Hernandez was also hospitalized, reportedly shot with a Taser during his arrest.

“All he had to do was present himself in court, pay a few fines, and then this happens,” said Cruz.

Another person was taken into custody at the scene, though it’s unclear what charges he or she may face.

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Later Thursday night, a crowd of protesters gathered outside Maimonides Hospital in Borough Park. Diaz’s mother, brother and girlfriend stood outside in solidarity.

Jorge Islas, the Consul General of Mexico, confirmed Diaz was in the country legally on a visa, but said Avendano-Hernandez was undocumented.

“I was told that he’s a not-documented migrant, so that I think whenever the medical supervision is over and he’s OK, he’s going to face trial in the court,” Islas said.

Elected officials said ICE has a lot more to explain, given the way the situation played out.

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“I think it’s completely a disgrace that someone is going to pull a gun to someone that has no gun,” State Assembly Member Felix Ortiz said.

“The message for ICE, we don’t want you here,” NYC Public Advocate Jumaane Williams said.

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In a statement, ICE said its officers were physically confronted and that a member of its fugitive operations team discharged at least one firearm. Two agents were treated for minor injuries.