A police car drives by the house, on left, where former Bosnian Serb wartime general Ratko Mladic was found in the village Lazarevo, about 50 kilometers north of Belgrade, Serbia, Saturday, May 28, 2011. Bosnian Serb genocide suspect Ratko Mladic was arrested on Thursday in this village after 16-years on the run.
"We will continue to pursue all those who have helped Mladic and other fugitives evade justice," Serbian war crimes prosecutor Vladimir Vukcevic told AFP.
"By hiding Mladic they have caused serious damage to this country. Hiding fugitives from the Hague tribunal is a serious crime," he added.
As officials said they were stepping up security ahead of a planned protest by ultra-nationalists against Mladic's arrest on Sunday, his lawyer said Mladic was urging calm.
"He is appealing to people to calm down, there should be no bloodshed, he does not want to be a cause of unrest," Milos Saljic told reporters.
"He appeals for there to be no riots, for everything to be peaceful," Saljic said.
The lawyer also suggested Mladic was resigned to being transferred to the International Criminal Tribunal for the former Yugoslavia (ICTY) in The Hague.
He was "aware he would be sent" to the UN court, Saljic said, adding: "He does not know when, but he would like to get some rest before that."
Mladic, accused of masterminding the 1995 Srebrenica massacre and other atrocities during the 1992-95 Bosnian war, was arrested Thursday and is set to be transferred to the ICTY next week.
His lawyer is expected to launch an appeal on Monday against a ruling that he is fit to stand trial and be transferred to the international court, where he faces charges of war crimes, genocide and crimes against humanity.
Mladic's capture came amid many questions as to how Europe's most-wanted man was able to evade his pursuers for so long.
Serbian authorities insist there was no collusion but the opposition has suggested that some in the security forces in Serbia -- where many see Mladic as a war hero -- were involved in protecting him.
President Boris Tadic told the BBC Friday that authorities would leave no stone unturned in their search for those who sheltered Mladic.
"We'll extend our investigation to see how he created a protection system or to see if it is possible that some people from the former armed forces or police were involved in the protection," he said.
Tadic promised a "full and complete picture" of the network.
Interior Minister Ivica Dacic meanwhile said security had been stepped up after the ultra-nationalist Radical Party (SRS) called for the massive protest in Belgrade on Sunday.
"The police will not use force in advance ... only if there is a drastic violation of public peace and order," Dacic told journalists.
"Security measures have been increased to a higher level," he said, including around state buildings and embassies.
After the arrest of Bosnian Serb wartime political leader Radovan Karadzic in July 2008, thousands of ultra-nationalists violently protested in Belgrade, leaving one dead.
The Serbian press also revealed fresh details of Mladic's arrest after intelligence officers and a special team tracking war criminals swooped on Lazarevo, a village around 80 kilometres (50 miles) north of Belgrade.
Found in a house belonging to a relative, Mladic was an oddly welcoming host when security forces finally tracked him down, media reports said.
Dacic told RTS television that Mladic said to the arresting officers: "Congratulations guys, you found the one you've been looking for."
Blic newspaper reported that he told a relative when the team arrived: "Branko, give these people something to drink and eat. Here this is my ID card and military record. It is over."
The team was served ham, cheese and home-made brandy, Blic reported. Asked whether he was armed, Mladic reportedly said: "What kind of general would I be if I was not armed? Here are my two pistols. All these years I've had them with me all the time."
The ICTY indictment holds Mladic responsible for the Srebrenica massacre, Europe's deadliest atrocity since World War II, in which 8,000 Muslim men and boys were rounded up and killed.
It also accuses him of having overseen the 44-month siege of the Bosnian city of Sarajevo, during which 10,000 were killed.
News of Mladic's arrest was largely welcomed around the world, but some protests have erupted in the region following his detention.
About 500 ultra-nationalists in the northern Serbian city of Novi Sad protested on Thursday, and some 2,000 demonstrators gathered Friday in the Bosnian Serb town of Pale.