By Ray Sanchez, CNN
(CNN) -- A mass shooting with 12 people dead is probably the last way that Geoff Dean wanted to end his 40 years with the Ventura County Sheriff's Office.
Dean is stepping down after seven years as sheriff just as a gunman went on a rampage Wednesday night at the Borderline Bar & Grill in Thousand Oaks, California.
"It's a horrific scene in there," the sheriff said early Thursday.
Near the end of a news conference later Thursday, Dean casually told reporters he was retiring at midnight Friday.
"But I will certainly be a part of the family."
That family included Ventura County sheriff's Sgt. Ron Helus, who was among those killed at the bar late Wednesday.
Helus, 54, had been with the department for nearly three decades and was nearing his retirement, Dean said.
"They're mourning," he said of the sheriff's office, which has about 700 officers. "They're sad. It's awful. Ron was a great guy. He was close to everybody. He was a hard worker, and our hearts are broken all over."
A lifelong Californian, Dean was born in Los Angeles and raised in Simi Valley, according to the sheriff's office website.
He and his wife of 31 years, Marlene, have two children: Lindsey 29, an attorney, and Andy 26, who works in marketing and sales.
"We've got to do something about the hate," Dean recalled telling members of a local synagogue after the mass shooting at Tree of Life synagogue in Pittsburgh.
"And we've got to do something to just spread the love and reach out and help people and be patient with them and understand them because this will touch so many lives around our community."
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