BAY HARBOR ISLANDS, Fla. -

A 66-year-old doctor was charged with animal cruelty with intent to kill after Bay Harbor Islands police said he killed a dog after repeatedly hitting it on the head with a hammer before stabbing it with a screwdriver.

Isaias Lerner, MD was arrested Tuesday.

According to an arrest affidavit, witnesses told police they saw a dog tied to a tree outside his home in the 10300 block of East Broadview Drive on Tuesday morning. The witnesses said an older man, identified as Lerner, repeatedly hit the dog in the head with a hammer and then stabbed the dog with a screwdriver in what they described as a grinding motion. Brain matter appeared to be coming out of the dog's head, the witnesses told police.

Neighbors were stunned by the news.

"I have been their neighbor for twelve years. 'So you've seen the dog?' Yeah, it comes in my garbage all the time," said one woman. "My dogs, they bark between the gate. I'm sad. It's just a benign dog that's sweet."

According to the arrest affidavit, Lerner told police he hit the dog with a hammer several times. He said the dog wobbled around before dying.

The arrest affidavit says Lerner is a doctor with the South Broward Physicians Group, 1487 Lyons Rd. in Coconut Creek, which was closed Wednesday.

"It sounds totally irrational -- not like him," said one patient.

"To me, I am shocked," said Dr. Albert Morjaim, who said Lerner was his professor in medical school. "To do harm to any animal, to do harm to anybody, and as a physician, it disgraces my profession."

Lerner was out of jail on Wednesday.