A 175-pound dog, declared dangerous two months ago by St. Paul officials, clamped its jaws on the head of a toddler at the girl's home in the animal's third violent confrontation with a small child in the past two years, authorities said Friday.

Thursday night's attack by the Presa Canario mastiff on 18-month-old Clara Marie Ryan occurred at the family's home in the 900 block of Mendota Street, sending her to the hospital and leaving the dog under guard at Animal Control, police said.

Police spokesman Sgt. Paul Paulos said the dog, named Blue, is current on its vaccinations. Clara's grandfather, Adam Dyer, said she was treated for her injuries and is being hospitalized overnight as a safety precaution. Clara received several stitches, he said.

"There was a dog bite in the face," said Dyer, Blue's owner. "She's a baby. I mean, it looks bad.

"She is doing very well."

At the time, the dog was being petted by a 4-year-old girl, who shares a grandmother with the victim. Clara approached "and might have surprised the dog, and he turned around and grabbed her by the head," Paulos said.

An officer questioned the girls' grandmother as she held a wounded Clara, Paulos said. The officer said he saw a cut above the girl's eye and a "possible puncture mark" underneath the eye, Paulos added.

Dyer said he believes something startled the 2-year-old dog, and that it did not act out of aggression. Clara and Blue were close and familiar with each other, he said.

"She used him as a pillow," Dyer said. "My dog is not a wild animal."

In addition to weighing the animal's fate, authorities were assessing whether any charges are warranted.

This is the second time this year that police were called to the home in the Payne-Phalen neighborhood about the 2 1/2-year-old male dog harming a child, Paulos said.

The dog clawed Clara's 6- or 7-year-old brother on Jan. 2 after the boy came into contact with skin on Blue that was infected, according to police and city records. The boy was cut on the face, inside the mouth and on the left arm, the records added.

It was that confrontation that elicited the dangerous-dog declaration, said Ricardo Cervantes, director of the city's Department of Safety and Inspections.

Dyer, who lives at the home on Mendota, is appealing that ruling.

"From what I read in the police report," Cervantes said, "the owner might not want to recover the animal."

If the dangerous animal declaration stands, "then the dog would be destroyed" as soon as 10 days from Thursday's incident, Cervantes added.

"It bugs me, but my granddaughter is more important than my dog," Dyer said, adding that he understands that euthanasia might be the only option.

Police and city records also show the dog inflicted injury on the same brother in March 2010, leaving the boy with a tooth puncture on his face.

In that incident, Cervantes said, the brother stepped on the dog's genitals.

Blue responded with a "natural reaction," leading to the boy and the dog bumping heads. At that point, one of the dog's teeth punctured the boy's cheek.

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