Bristow, Virginia (CNN) -- Homeland Security Secretary Janet Napolitano has ordered an investigation after a man who was in the United States illegally killed a nun in a car crash, authorities said. 

Napolitano is trying determine why the man was still in the country because he had been arrested two previous times for drunken driving offenses. 

The suspect, Carlos Montano, driving Sunday morning under the influence of alcohol, slammed head-on into three nuns in a Toyota sedan, police said. The three were just a few miles from a monastery in Bristow, Virginia, heading for their annual retreat. Sister Denise Mosier was killed instantly, and the other two remained hospitalized Tuesday. 

The suspect has twice been in custody -- the first time, almost two years ago in October 2008 -- Immigration and Customs Enforcement officials said. But both times, Montano was released on his own recognizance pending deportation proceedings, because he was not convicted of a violent felony such as murder, rape, or robbery. 

"He was in removal proceedings," Napolitano told CNN on Tuesday. "Why were the removal proceedings taking so long? I do not obviously as of today have the results of that, but I will get them." 

Corey Stewart, chairman of the Prince William County Board of Supervisors, said he was furious with how immigration officials have handled the case. 

"We identified him as an illegal alien, we told ICE that he had twice been convicted now of DUI's, that he posed a threat to the community," said Stewart. "And they turned around and they released him right back into the neighborhood." 
Who ordered the inquiry?
What is her job?
What did the accused do?
What was his name?
Is he white?
Does he have previous convictions?
What were they?
How many churchwomen were there?
Did they all die?
Where were they headed?
was this incident taken care of correctly?
Why wasnt he deported?
Janet Napolitano
Homeland Security Secretary Janet Napolitano has ordered an investigation
Homeland Security Secretary
Homeland Security Secretary Janet Napolitano
killed a nun in a car crash
killed a nun in a car crash
Carlos Montano
The suspect, Carlos Montano
unknown
unknown
yes
he had been arrested two previous times for drunken driving offenses. 
drunken driving offenses.
two previous times for drunken driving offenses. 
Three
slammed head-on into three nuns
no
Sister Denise Mosier was killed instantly, and the other two remained hospitalized Tuesday. 
Bristow, Virginia,
just a few miles from a monastery in Bristow, Virginia,
no
said he was furious with how immigration officials have handled the case. 
because he was not convicted of a violent felony such as murder, rape, or robbery
because he was not convicted of a violent felony such as murder, rape, or robbery