An elderly man and a teenage boy were injured Thursday morning in a series of dog attacks, the Pasco County Sheriff's Office said.Deputies initially responded around 6:53 a.m. Thursday to a report of five dogs – three adult bulldogs and two puppies – attacking a 15-year-old boy and an elderly man at two different places in Shady Hills. The man has serious injuries, the sheriff’s office said.One of the dogs bit the boy on the leg either while he walked to school or was waiting for the bus, the sheriff’s office said. The boy’s injuries are considered minor.A Pasco County deputy shot one of the dogs after it tried to attack him, the sheriff's office said. Authorities euthanized the dog that was shot at the request of the owner, but the deputy was not injured.Two of the other dogs involved in the attack are in custody of Pasco County Animal Services. The two puppies at the scene were not involved in the attack, according to the sheriff's office. The two puppies were returned to their owner.Animal Control is on the scene to take control of the dogs. All five dogs belonged to the same owners.