The first officer who responded to a mass shooting in Boulder was killed. He leaves behind seven children

(CNN) — The 21-year-old suspect in Monday’s massacre at the King Soopers supermarket in Boulder, Colorado, faces 10 counts of murder in the first degree, Boulder Police Chief Maris Herold said Tuesday.

The 10 people who died ranged in age from 20 to 65, she said. That includes Boulder police officer Eric Talley, 51.

“We are going to do everything in our power to make sure this suspect as a thorough trial,” and a thorough investigation will be done, Herold said.

Talley was the first officer to respond to reports of an armed man inside a grocery store in Boulder, Colorado, on Monday — and it’s where the father of seven died after actions that were described as “heroic” by officials.

• Officials: Gun in supermarket shooting bought 6 days earlier
• Colorado shooting victims included store workers, officer
• Boulder supermarket shooter ID’d as 21-year-old man
• Officer killed in Colorado mass shooting was Ball State University grad
• Biden pushes House-passed gun reforms in the wake of Colorado mass shooting

Talley, 51, had been a member of the force since 2010, according to Herold.

“Didn’t surprise me he was the first one there,” Talley’s father, Homer Talley, told CNN affiliate KUSA.

He is survived by his wife and seven children, the oldest of whom is 20, according to his father.

“He loved his family more than anything,” Homer Talley said.

He described his son was a prankster with a “great sense of humor,” the affiliate reported.

In 2013, Talley was among a small group of Boulder officers who made headlines after a duckling rescue from a drainage ditch. The officer had “waded into the calf-deep water to try to round up the ducks” and save them, the Daily Camera newspaper in Boulder had reported.

Talley is the first officer from the Boulder police department to be killed in the line of duty since 1994 and the sixth on-duty death in the department’s history, according to the National Law Enforcement Officers Memorial Fund.

According to KUSA, Homer Talley said his son had recently been looking into becoming a drone operator because he believed it was safer.

He was the first on scene

Talley arrived on scene just minutes after the first 911 calls came in reporting shots fired around 2:30 p.m. local time, Herold said Monday night.

“I have to tell you the heroic action of this officer when he responded to the scene,” the chief said, adding that Talley responded after “a phone call about a possible person with a patrol rifle.”

“Officer Talley responded to the scene, was first on the scene, and he was fatally shot,” Herold said.

The fallen officer “served in numerous roles supporting the Boulder Police Department and the community of Boulder,” the chief told reporters.

He was remembered as “one of the outstanding officers” by the county’s district attorney.

“My heart goes out to Eric Talley’s family, his loved ones, and his colleagues,” Boulder District Attorney Michael Dougherty said. “He was, by all accounts, one of the outstanding officers of the Boulder Police Department, and his life was cut far too short, as he responded to the shooting that was taking place at King Soopers.”

Multiple law enforcement agencies held a rolling vigil in Talley’s honor Monday night.

Local, state and federal partners are all working on the investigation into the shooting, along with prosecutors from the US Attorney’s Office “to ensure that justice is done,” Dougherty told reporters.

“I promise the victims and the people of the state of Colorado, that we will secure justice and do everything we must do to get justice in this case, in order for that to happen, a painstaking investigation is already underway, both at the crime scene and in interviews to make sure we receive all the accurate information,” the district attorney said.

“For all the victims who were killed at King Soopers, these were people going about their day, doing their food shopping, and their lives were cut abruptly and tragically short by the shooter, who is now in custody,” Dougherty added.