Mental illness is "a massive problem," GOP front-runner Donald Trump said Thursday, one day after two Virginia journalists were brutally murdered by a disgruntled former co-worker, but he does not believe there is any need to get rid of guns."If you try to do it, the bad guys would have them," Trump told CNN's "New Day" host Chris Cuomo , saying that instead, the focus should be on solving the mental health issues. Former reporter Bryce Williams , whose legal name is Vester Flanagan, killed himself Wednesday afternoon after shooting to death TV reporter Alison Parker and her cameraman, Adam Ward, during a live broadcast for WDBJ-TV station in Roanoke, Virginia."He was definitely borderline and would have been and should have been institutionalized at some point," Trump said Thursday morning. "I wish people closest to him would have seen it, but people are being released now because they don't have any money ... this was a very sick man."And it's just too bad that we can't figure these things out beforehand. I mean, everybody sees the signals but nobody thinks a thing like this could happen."But still, he said, it's a dilemma about what to do with the mentally ill."What are you going to do, put them in jail for the rest of their life?" Trump said. "There were lawsuits and litigation on all sorts of things with him. And he just blew up. He knew he was going to blow up, too, based on his memos and notes."Parker's father, Andy Parker, told Fox News on Wednesday night that while talk of his daughter's death will fade away, he promises to do "whatever it takes to get gun legislation to shame people, to shame legislators into doing something about closing loopholes in background checks and making sure crazy people don't get guns.'"But Trump said he is not sure gun control laws would have helped."He snuck up on them, whether it was a gun or a knife or whatever it would have been, it would have been something," Trump said. "I'm a very much 2nd Amendment person, and I know the arguments both ways very well, but I'm very much into the 2nd Amendment. You need protection."But, he said, every time there is a shooting, "they go into the background of these people that do the shooting. And people that do them and were close to them, you know, 59 percent of the time they say — 95 percent of f the time — they say, I really can understand how that happened. He was off the edge."