(CNN) -- Federal undercover agents in Arizona fired Thursday into a car carrying five males whom they were investigating, hitting two of them, said Tom Mangan, a special agent with the Bureau of Alcohol, Tobacco, Firearms and Explosives.
The incident occurred as the agency's undercover unit was planning to arrest the five males -- all suspected robbers -- in a parking lot in central Phoenix, he said. After the agents detonated a flash-bang grenade intended to surprise the suspects, some of them attempted to flee in their black, four-door compact car, he said.
"SWAT team members felt they were in danger and fire[d] into the vehicle hitting the driver multiple times, a second passenger was also wounded," he said.
The driver's condition was not known; the other person was expected to recover, he said.
A third person said he suffered superficial wounds caused by flying glass, Mangan said.
The first court appearance for the suspects was slated for Friday before a federal magistrate.
The incident is being reviewed by the Phoenix Police Department.
Mangan said the ATF entered the investigation as part of an investigation into violent crime and kidnappings in the Phoenix area.
CNN's Greg Morrison contributed to this story.