The US Department of Justice (DoJ) has ordered a second anti-trust inquiry into Google’s plan to take over web-based travel services technology ITA Software. 

The inquiry. which is to be conducted by the US federal authorities, is regarding the projected market consolidation and displacement of other related businesses, small and big, following Google’s announcement to integrate travel services directly into its search results page, the Wall Street Journal has reported.

“We know that closer scrutiny has been one consequence of Google's success, and we said that we wouldn't be surprised if there were a regulatory review before the deal closes," said Andrew Silverman, a Google senior product manager in a blog post. 

Started by computer researchers at the Massachusetts Institute of Technology, ITA Software provides technology for airline reservation system, and has a headcount of more than 500 employees. 

The deal, which will allow Google to enable its users search for flights, find fare within their budget and block tickets, is expected to impose a serious threat to other online travel experts such as Expedia, Travelocity and Orbitz.