“We will be talking to all the parties that have shown interest in the club”
Administrator Bryan Jackson
The Hearts board had requested KPMG to be appointed administrators but the Court of Session in Edinburgh selected BDO, the choice of the bankruptcy administrator of Ukio Bankas, who hold the floating charge over the club.
Trevor Birch will head up the BDO operation with assistance from Jackson, who is also overseeing the administration process at Dunfermline Athletic.
Birch is a former Chelsea chief executive and worked on finding a buyer for Portsmouth last year.
Hearts are due to pay a six-figure sum to the Inland Revenue on Friday but have insufficient funds available.
They also have a VAT bill due to be paid at the end of this month and must pay the balance, thought to be about £50,000, outstanding from last month's PAYE bill.
Hearts employ 131 people, including a first-team pool of 26, with 10 players remaining in the youth set-up.
Hearts in financial trouble
Feb 2005 - Vladimir Romanov takes a controlling stake at Tynecastle
Season 2005/06 - Hearts finish second in the SPL
Hearts win Scottish Cup in 2006 & 2012
Wage delays become a regular feature from 2011 on
Nov 2011 - Romanov seeks a buyer for club, saying he has has invested more than £50m
October 2012 - SPL imposes registration ban for repeated late payment of salaries
May 2013 - Ukio Bankas declared bankrupt
May 2013 - UBIG unable to meet its liabilities
May 2013 - Hearts avoid points deduction as SPL rules UBIG has not suffered an insolvency event
June 2013 - Hearts enter administration
Jackson said: "I can confirm that we have today been appointed administrators of Hearts. Fans will, inevitably, be concerned about these developments and none of them will have wanted this moment to arrive.
"We will now undertake an urgent examination of the company's records prior to making any further announcements.
"We are acutely aware of the need for speed in this process given the uncertainty of the last few weeks and the proximity of the season's start. We will be talking to all the parties that have shown interest in the club in order to find a resolution as quickly as possible."
In a letter to Hearts staff seen by BBC Scotland, director Sergejus Fedotovas says he hopes employees "will get deserved recognition and will be treated well under the new regime".
The liquidator of Ukio Bankas can sell the 29.9% shareholding it has in Hearts, as well as Tynecastle Stadium, which was held as security for the debt.
In addition, another £10m is due to UBIG. A liquidator with the power to sell UBIG's Hearts shares will only be appointed if the company's bankruptcy is formalised.
Scottish First Minister Alex Salmond, a supporter of the club, said he fully expected Hearts to survive their difficulties.
Interview - Bryan Jackson
"The situation affects fans like myself and players, but Heart of Midlothian is a substantial employer in the city," he told business leaders in Edinburgh.
"Like other clubs who've gone through that process, it's a great time of anxiety for the employees of Heart of Midlothian.
"One comfort I would have at this time is that other clubs have gone through it and emerged at the other end of the tunnel, and that's what I fully expect Heart of Midlothian to do.
"They've been around for a long time and I'm sure they'll be around for a long time to come."
An American consortium who were interested have decided to withdraw their interest. The group from New York have decided to withdraw partly because of the decision by the club to enter administration but also due to the uncertainty over the 50% shareholding by UBIG in the Hearts.
There are still two groups from America interested in taking over Hearts and both are expected to make representations in the coming days.
Top-flight rules state any club suffering an insolvency event will be stripped of 10 points or a third of their previous season's tally, whichever is the greater. Hearts finished the last campaign in 10th place with 44 points.
Hearts avoided a points deduction and possible relegation in May after the SPL decided the club's financial problems had not breached its rules before the end of the season.
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