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                                  NEWS RELEASE

DATE:           September 28, 2005     5:00 p.m. E.S.T.
CONTACT:        James L. Saner, Sr.  President and CEO
                MainSource Financial Group  812-663-0157

                Ronald B. Scott  President and CEO
                Peoples Ohio Financial Corporation  937-339-5000

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        MainSource Financial Group and Peoples Ohio Financial Corporation
                          Announce Definitive Agreement

MainSource   Financial  Group,   Inc.,   Greensburg,   Indiana  (Nasdaq:   MSFG)
("MainSource"),  and Peoples Ohio Financial Corporation,  Troy, Ohio (OTC: POHF)
("Peoples"),  today jointly  announced  that they have entered into a definitive
agreement to merge Peoples into MainSource.  Peoples'  subsidiary bank,  Peoples
Savings Bank of Troy ("Peoples Savings"),  will be merged  simultaneously into a
newly-formed subsidiary of MainSource.

The Agreement provides that shareholders of Peoples will have the right to elect
to receive cash in the approximate  amount of $5.60 per share, or  approximately
0.3068 shares of MainSource common stock (valued at $5.60, based on MainSource's
September 27, 2005 closing  price) for each share of Peoples  common stock owned
by them.  Based on  MainSource's  September 27, 2005 closing price and including
the anticipated cash out of certain Peoples stock options, the transaction value
is estimated at $41,750,000.

The amount of cash or stock payable to Peoples'  shareholders may be adjusted at
the time of closing  based on the value of Peoples'  consolidated  shareholders'
equity as of the end of the month prior to closing,  after  certain  adjustments
prescribed  by  the  agreement   have  been  made,  and  the  closing  price  of
MainSource's  common  stock  prior to  closing.  However,  75% of the  aggregate
consideration  must be paid in shares of MainSource  common stock, and there may
be  allocations  of cash or  stock  made to  shareholders  (on the  basis of the
smallest  to the  largest  shareholders)  to  ensure  that this  requirement  is
satisfied.

The  transaction,  which is expected to close in the first  quarter of 2006,  is
subject  to  various   regulatory   approvals   and  the  approval  of  Peoples'
shareholders.

The transaction is expected to be accretive to  MainSource's  earnings per share
during the first full year following the transaction. The transaction will allow
MainSource  to establish a presence in west central  Ohio.  MainSource  plans to
continue  to  operate  all of  Peoples'  current  offices  under  the  new  name
"MainSource Bank - Ohio."

James L. Saner, Sr., President and Chief Executive Officer of MainSource stated,
"This is our company's  first venture into Ohio, and we could not have partnered
with  a  better  bank  that  epitomizes  the  community  bank  philosophy.  This
Philosophy  is  demonstrated  every  day by the way  Peoples  takes  care of its
customers  and  its   communities."   He  added,  "We  are  committed  to  local
decision-making  and we stand firm on our  commitment to our  community  banking
philosophy.  Our current structure emphasizes  regionalized  management by local
employees, which serves as a cornerstone for MainSource."

Under the  Agreement,  Ronald B. Scott will remain as  President  and CEO of the
newly-named  entity,  and will  maintain  his office in the current  Troy,  Ohio
office of Peoples Savings in order to serve current Peoples Savings customers.

Ronald B. Scott,  President and Chief Executive Officer of Peoples,  stated, "We
believe  that  Peoples  is a  good  fit  with  MainSource.  As an  organization,
MainSource  does  small  town,  community  banking  on a larger  scale.  It is a
financial  services holding company  comprised of smaller  community banks which
together can be more competitive."

MainSource  Financial Group, Inc.,  headquartered in Greensburg,  Indiana,  is a
community-focused,   financial   services   holding   company   with  assets  of
approximately $1.7 billion.  Through its three banking subsidiaries,  MainSource
Bank,  Greensburg,   Indiana;   Peoples  Trust  Company,  Linton,  Indiana;  and
MainSource Bank of Illinois,  Kankakee,  Illinois,  it operates 55 offices in 23
Indiana  counties  and six  offices  in three  Illinois  counties.  Through  its
non-banking  subsidiaries,  MainSource  Insurance LLC,  MainSource Title LLC and
MainSource  Mortgage LLC, it provides various related financial services through
its banking affiliates.

Peoples  Ohio  Financial  Corporation  was formed in 2002 and  acquired  all the
shares of Peoples Savings Bank of Troy.  Peoples Savings has been  headquartered
in Troy, Ohio since its  establishment  in 1890 and operates six offices located
in Miami and Northern Montgomery  Counties.  Peoples had $199.9 million in total
assets and $25.4  million  in total  shareholders'  equity and equity  from ESOP
shares as of June 30, 2005.

Forward-Looking Statements

Except for historical information contained herein, the discussion in this press
release may include  certain  forward-looking  statements  based upon management
expectations.  Factors  which  could cause  future  results to differ from these
expectations include the following: general economic conditions; legislative and
regulatory initiatives;  monetary and fiscal policies of the federal government;
deposit flows;  the costs of funds;  general market rates of interest;  interest
rates on competing investments;  demand for loan products;  demand for financial
services;  changes in  accounting  policies  or  guidelines;  and changes in the
quality or composition of the MainSource's loan and investment  portfolios;  the
timing of the closing of the transaction;  the timing and success of integration
efforts once the transaction is complete;  MainSource's  expectations or ability
to realize  success  with the  acquisition  of  Peoples,  and the impact of this
transaction, if successful, on MainSource's business.

The forward-looking statements included in the press release relating to certain
matters  involve  risks  and  uncertainties,   including  anticipated  financial
performance,  business  prospects,  and other  similar  matters,  which  reflect
management's best judgment based on factors currently known.  Actual results and
experience  could  differ  materially  from  the  anticipated  results  or other
expectations expressed in the Company's  forward-looking  statements as a result
of a number of factors,  including  but not limited to,  those  discussed in the
press release.

MainSource  will be filing a  Registration  Statement on Form S-4 concerning the
merger with the Securities and Exchange Commission  ("SEC"),  which will include
the  proxy  statement  that will be mailed  to  Peoples'  shareholders.  WE URGE
INVESTORS TO READ THESE DOCUMENTS  BECAUSE THEY CONTAIN  IMPORTANT  INFORMATION.
Investors  will be able to obtain the documents free of charge,  when filed,  at
the SEC's website,  www.sec.gov.  In addition,  documents  filed with the SEC by
MainSource  will be available free of charge from the Secretary of MainSource at
201 N. Broadway,  P.O. Box 87, Greensburg,  IN 47240,  telephone (812) 663-0157.
Documents  filed with the SEC by Peoples will be  available  free of charge from
the Secretary of Peoples at 635 South Market Street, Troy, Ohio, telephone (937)
339-5000.  INVESTORS  SHOULD READ THE PROXY STATEMENT  CAREFULLY BEFORE MAKING A
DECISION CONCERNING THE MERGER. Copies of all recent proxy statements and annual
reports are also  available  free of charge  from the  respective  companies  by
contacting the company secretary.

MainSource and Peoples and their respective directors and executive officers may
be deemed to be  participants  in the  solicitation  of proxies  to approve  the
Merger.  INFORMATION  ABOUT THE  PARTICIPANTS  MAY BE OBTAINED THROUGH THE SEC'S
WEBSITE  FROM THE  DEFINITIVE  PROXY  STATEMENT  FILED WITH THE SEC ON APRIL 29,
2005,  WITH RESPECT TO MAINSOURCE AND THE DEFINITIVE  PROXY STATEMENT FILED WITH
THE SEC ON SEPTEMBER 24, 2004, WITH RESPECT TO PEOPLES.

For more information contact:

                                    * * * * *

 MainSource Financial Group, 201 N. Broadway, P.O. Box 87, Greensburg, IN 47240

                                       or

  Peoples Ohio Financial Corporation, 635 South Market Street, Troy, Ohio 45373