Deleting a Row from a Time Indexed Dataframe

I'm trying to delete a row in a Pandas dataframe by simply passing the date and time.

The dataframe has the following structure:

Date_Time             Price1   Price2    Price3                       
2012-01-01 00:00:00    63.05    41.40    68.14
2012-01-01 01:00:00    68.20    42.44    59.64
2012-01-01 02:00:00    61.68    43.18    49.81

I have been trying with df = df.drop('2012-01-01 01:00:00')

But I keep getting the following error message:

exceptions.ValueError: labels [2012-01-01 01:00:00] not contained in axis

Any help on either deleting the row or just deleting the values would be much appreciated.

:-)