DETROIT (WJBK) -- Andy Arena became the special agent in charge at the FBI in Detroit in 2007. He was back home where he grew up and ready to take on crime in the Motor City.
However, who could have guessed the kind of cases his office would encounter from an attempted terrorist attack on Christmas Day to the killing of an imam in Dearborn to the search for missing children to the public corruption cases making national headlines.
After five years on the job, Andy Arena is reflecting.
"There were points where I thought the office was at a breaking point. The stress that these people endured was incredible," he said.
2009 was especially hard with the death of Agent Paul Sorce in a car accident and a whole host of high profile cases like Umar Farouk Abdulmutallab's alleged attempt to blow up Flight 253.
"Right in the middle of it you have the underwear bomber, and that was probably, in retrospect, the highest profile case that this office has ever worked in its history," Arena explained. "They stepped up when the bell rang to defend their country."
Highs and lows -- Arena and his agents faced fierce criticism after a raid and attempted arrest of Imam Luqman Abdullah on suspicion of conspiracy and firearms. That led to his death. He was shot 21 times.
A Department of Justice investigation found the agents were justified, but Arena still thinks about what happened.
"I still think back on that day and I think what could we have done different, but at the end of the day my agents went home and those were difficult decisions. I made them. I stand by them, and I, quite frankly, have to live with them," he said.
It's been a busy five years. The arrest of the Hutaree militia members, the explosion of health care fraud with more than 160 people indicted in the past year alone, and then there are the missing children -- Tangena Hussain, the three Skelton brothers missing from Morenci, Bianca Jones -- all unsolved.
"People tend to forget. Like I said, we never forget," Arena told us.
And they never stop working those cases like the murder of Nevaeh Buchanan in Monroe. Arena has a daughter the same age.
"I'd go to work in the morning, and she'd say, 'Daddy, go find that little girl.' And that's very emotional for all of us," said Arena.
Buchanan was found murdered and buried in a hole covered in cement along the bank of the River Raisin.
"The missing kids -- you can recall like they were yesterday. They're the cases that stay with you the rest of your life. They haunt the investigators that worked them," Arena explained.
However, the agents are taxed with far more cases. Detroit ranks in the top five of every investigative program in the FBI -- violent crime, gangs, health care fraud, mortgage fraud and public corruption.
"I made a statement about look over your shoulder, look under your bed, and people snickered at that. Well, I don't think they're snickering now. That was not a joke. I was serious," Arena said.
"How strong is this case against Kwame and company?" FOX 2's Amy Lange asked him.
"We'll see in court. It's coming up," he replied.
Kwame Kilpatrick is not the only big one for the FBI right now. Wayne County Executive Robert Ficano is also under investigation.
"We are going to push this investigation as quickly as possible," said Arena.
Extra agents and additional lawyers from the U.S. Attorney's Office are assigned to the case.
"I think we owe it to the taxpayers of Wayne County. We, quite frankly, owe it to the people who are under investigation to either clear their name or bring charges forward," Arena told us.
Arena will be eligible for retirement in the spring, but isn't committing to anything other than Detroit, as was his pledge five years ago when he came back.
In that time, Arena says the state of Michigan has lost 3,000 police officers to budget cuts. Over at the FBI, he's increased his ranks by 40 agents and 60 support staff positions. Those are resources he says he wants to use to try to help this struggling city.
"As the city deals with their financial issues, we got to stand and we got to be there for the city. They need our help, and we got to give them everything we can," said Arena.