The suspect killed in an officer-involved shooting in Alton fired at deputies 15 times, according to Hidalgo County Sheriff Eddie Guerra.

Guerra held a press conference at the Hidalgo County Sheriff's Office on Tuesday to provide further details on the shooting linked to a homicide investigation out of Mission.

Guerra said 51-year-old Paulino Guerra Jr. shot at deputies after they attempted to execute a search warrant at his residence in Alton in connection with a deadly drug deal gone wrong.

Deputies returned fire, killing Paulino.

"This weekend's incident is a clear reminder of how crucial preparation is. The protective gear and constant training of deputies provide a constant role in saving lives during this crucial incident," Guerra said. "As law enforcement officers, we are committed to being peacekeepers, serving and protecting every member of our community with integrity, compassion and professionalism."

The incident occurred on Saturday when deputies found 36-year-old Felipe Mancilla lying on a roadway at the 2400 block of Venecia Street with multiple gunshot wounds.

Guerra said investigators believe Paulino shot at Mancilla with a 9mm handgun in a drug deal gone wrong.

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According to Guerra, Paulino was trying to buy drugs from Mancilla when he shot and killed him.

Authorities found Paulino in at bedroom of his home when he shot 15 rounds at deputies, according to Guerra.

A Hidalgo County sheriff's deputy was struck three times during the shooting. He was struck once in his Kevlar helmet, on his "duty magazine" and on his radio transmitter, according to Guerra. Shrapnel from the transmitter struck the deputy's upper left arm.

The injured deputy was treated on scene and transported to DHR Health for non-life threatening injuries, according to Guerra. The deputy has since been released and is expected to make a full recovery.

As previously reported, Alton Police Chief Mark Perez said since 2018, there have been 20 service calls made to Paulino's residence, but no arrests were made.

Guerra said Paulino did suffer from mental health issues and had a lengthy criminal history. He has been arrested on multiple charges including drug charges, human smuggling and engaging in organized criminal activity.

Guerra said investigators believe Paulino reloaded his weapon following the deadly shooting in Mission, and was found with 20 extra rounds inside his pockets following the shooting with deputies.

"Let me be absolutely clear, if you choose to engage in the lives, to endanger the lives of our deputies, there will be serious consequences, up to and including the use of deadly force," Guerra said. "We will not hesitate to defend ourselves, we will not hesitate to defend our community from violent threats. Our deputies are highly trained, equipped and ready to respond with the appropriate level of force to ensure the public safety."