Priceline, the online travel booking company announced on Thursday its CEO Darren Huston has resigned following an internal investigation into a personal relationship with an employee who was not under his direct supervision. However, still the relationship within the company was a violation to its code of conduct.

Priceline said Huston has "acknowledged" the relationship and has also "expressed regret". However, the company did not give out further details regarding the relationship or the ongoing investigation.

The online company that helps people book hotels, flights and rent apartments is looking for a permanent successor. For the time being chairman and former CEO Jeffery Boyd is taking the helm as interim CEO and president. Boyd was Priceline Group Inc's president and CEO for more than ten long years from 2002 to 2013.

Huston, 50, was the company's CEO for over two years. He has worked with Pipeline for almost five years after a stint with Microsoft Corp. Priceline has headquarters in Norwalk, Connecticut but Huston worked from the Amsterdam office. The company said that, Huston will not get severance pay.

Under Huston Priceline bought OpenTable, an online restaurant reservation company for $2.6. It was a move meant to grow Pipeline's array of business outside hotel bookings.