Several top-tier B-schools that discovered they were hacked have decided to reject those hackers' applications, media reports said.

"This behaviour is unethical at best, a serious breach of trust that cannot be countered by rationalisation," Kim Clark, Dean of Harvard Business School, said in a statement. "Any applicant found to have done so will not be admitted."

Harvard said it knew the names of the 119 applicants who tried to learn their admissions status early using a security flaw in an online college-recruitment and application product called 'Apply Yourself'.

A policy of refusing admission to hackers has been gradually spreading and MIT's Sloan School of Management decided Tuesday to reject 32 applicants who hacked into their files to view confidential data on their applications, The Boston Globe reported.

It all started just after midnight on March 2, when an unidentified person posted instructions on an online site with instructions on ways to infiltrate the 'Apply Yourself' confidential files.

The business schools use independent website 'Apply Yourself Inc' for the application process.

Over the next nine hours, about 150 prospective students followed a simple procedure -- pasting a URL address into a Web browser and typing in a pass code -- in an attempt to learn their fate.

Almost everyone saw only a blank screen -- but the consequences were severe. Harvard Business School, the MIT Sloan School of Management, and Carnegie Mellon University's Tepper School of Business have pledged to reject any applicants who tried to get an early peek at their acceptance or rejection letter.

"The instructions are reasonably elaborate," MIT Dean Richard Schmalensee told 'The Boston Globe'.

"You don't need a degree in computer science, but this clearly involved effort. You couldn't do this casually without knowing you were doing something wrong. We've always taken ethics seriously, and this is a serious matter."

Schmalensee said that rejected applicants could apply in future years and the Sloan School will take into consideration any possible extenuating circumstances that might explain why a hacker infiltrated the 'Apply Yourself' files.

Other schools still evaluating the situation include Stanford, which said it is asking applicants whose files were hacked to explain their actions.