Ratko Mladic--'biggest killer since Hitler'--arrested

>>> we woke up today to learn they had caught one of the most wanted fugitives in the world. he orchestrated the slaughter of some 800,000 people. finally under arrest tonight and facing a war crimes trial. nbc news veteran foreign correspondent martin fletcher spent years covering this story and has more tonight on the capture of ratkomilotich.

>> he is called europe's biggest killer since adolf hitler . a fugitive for six years. today, in a black cap , looking frail, finally under arrest. it's over for the former leader of the bosnian serb army . 1999 , serbs are fighting muslims. don't worry, he tells the boy, we'll look after you. a lie. within hours, a massacre began. around 8,000 muslims murdered. at the same time, he led the siege in sarajevo. the longest siege in modern history . 10,000 dies from shells and snipers. justice indicted him for genocide and crimes against humanity but couldn't find him. at first, he hid in plain sight, attending weddings, soccer matches, visiting restaurants. head. he disappeared until today.

>> today, we arrested milanic. extradition process is on the way.

>> at dawn, swault te.w.a.t. teams moved in on the house. inside, milatic with two pistols, but he gave up.

>> i used to say his day will come. that was a decade ago. his day has come.

>> reporter: what a relief for the families of hivictims.

>> he's a monster, he says, a criminal. security sources in serbia tell nbc news for years he was protected by elements of serbia's secret services and the army. but no more. serb officials say in about a week, he will be turned over to the international court of justice . then, he'll finally be put on trial where he faces life in prison .

>> so many times we find these guys to find they're living in non-extraordinary circumstances. almost pathetic compared to how they used to be. why was he so hard to pin down?

>> the official sources i have been speaking to said he was looked after, protected by elements within the secret services , elements within the army for years. that then peelterred away over time , and over the last couple years, he was looked over by about a dozen friends of the family, people from before. in the end, he ended up in a small house looking after himself. finally surrendered without a fight. sick man, feeble. he's suffering.

>> a bad man in plain site in a small village. sounds familiar. like something we just went through. martin fletcher , thanks.