Mexicans protest detention of dogs in killings, tests come back negative

A puppy that was caught near the site of four fatal maulings sits inside a cage at a city dog pound in Mexico City,Wednesday, Jan. 9, 2013. Authorities have captured dozens of dogs near the scene of the attacks in the capital's poor Iztapalapa district, but rather than calm residents, photos of the forlorn dogs brought a wave of sympathy for the animals, doubts about their involvement in the killings and debate about government handling of the stray dog problem. (AP Photo/Dario Lopez-Mills) (The Associated Press)

One of the dogs that was caught near the site of four fatal maulings sits inside a cage at a city dog pound in Mexico City, Wednesday, Jan. 9, 2013. Authorities have captured dozens of dogs near the scene of the attacks in the capital's poor Iztapalapa district, but rather than calm residents, photos of the forlorn dogs brought a wave of sympathy for the animals, doubts about their involvement in the killings and debate about government handling of the stray dog problem. (AP Photo/Dario Lopez-Mills) (The Associated Press)

A litter of puppies that was caught near the site of four fatal maulings sit inside a cage at a city dog pound in Mexico City,Wednesday, Jan. 9, 2013. Authorities have captured dozens of dogs near the scene of the attacks in the capital's poor Iztapalapa district, but rather than calm residents, photos of the forlorn dogs brought a wave of sympathy for the animals, doubts about their involvement in the killings and debate about government handling of the stray dog problem. (AP Photo/Dario Lopez-Mills) (The Associated Press)

Dozens of protesters chanting "free the dogs, arrest the criminals!" say that about 50 stray dogs seized in connection with five deaths in a Mexico City park in recent weeks are innocent and should be released.

The city prosecutor's office says initial tests on the first 25 strays indicate there is no evidence they ate human flesh. However, officials are still awaiting results from tests on their fur to see if any human DNA was present on the dogs.

Since mid-December, the bodies of three women, a teenage boy and a baby have been found in a hilltop park with dog bites.

Protester Nominis de Esparza said Friday that protesters are convinced that humans killed the victims, not dogs. They say the dogs may have bitten the bodies after death.