Published Thursday, 10 October 2013
The Sinn Féin MLA made the statement following two separate murders in the space of 24 hours which have been blamed on dissident republicans.
First Minister Peter Robinson, meanwhile, said the conference would highlight the region's credentials as a good place to do business.
The two leaders were speaking ahead of a gala dinner at Hillsborough Castle to welcome delegates to the investment conference.
The event comes after the summer’s G8 conference in the Lough Erne Resort in Fermanagh, which was hailed as one of the most peaceful events in the summit’s chequered history.
But efforts by Mr Robinson and Mr McGuinness to showcase a positive image of Northern Ireland have been hit by the two separate murders in Belfast and Londonderry.
Mr McGuinness told UTV the timing of the two murders was “irrelevant”.
It is important potential investors get the right impression of a highly competitive, stable, investment location.
He said: “The important thing to say is that I absolutely unreservedly condemn the criminals responsible.
“In my opinion these people are of the same ilk as the criminals within the UVF who shot Jemma McGrath, just a few weeks ago.
"So I think the people who come to these investment conferences have a very clear view that this is a very successful peace process, one of the most successful peace processes in the world today."
“The killings of these people don’t challenge the institutions, they challenge the community.
“That’s why it’s important for the community to support the police in the apprehension of those responsible.”
He added: "This investment conference is an excellent opportunity to strengthen our bonds with existing investors and to warmly welcome potential investors who have taken the time to come and hear what we have to offer as an investment location.
"Foreign direct investment can bring many benefits to our community, by creating new jobs and helping to boost economic growth.
“It also generates additional opportunities within the local supply chain and leads to the expansion and growth of many home-grown businesses.
“The senior executives at the conference will find a business-friendly Executive ready to support international investment."
The investment conference is a direct result of the very positive impression made by Northern Ireland at the G8 Summit in June.
Mr Robinson told UTV there was sadness and horror in the wake of the two killings.
He added: “I think it will remind people of what it was like many years ago.
“There is an absolute resolve and determination that we can’t go back to the days of the past."
On the investment conference, the DUP leader said: “This is an opportunity to welcome the many senior executives, ambassadors and government representatives that have made the journey to be part of this investment conference, as well as current investors who have made such a valuable contribution to our economy.
"It’s a unique opportunity for us to begin building relations with key decision-makers, in the impressive surroundings of Hillsborough Castle.
“It is great chance for us to capitalise on the G8 and ensure that Northern Ireland retains a high profile worldwide."
© UTV News