Serbian authorities say they have arrested 750 people since the assassination of the country's prime minister last Wednesday.
The government announcement follows news of the arrest last night of two members of an underworld clan blamed for the murder of Zoran Djindjic.
Officials named the men as Mr Dragan Ninkovic and Mr Zoran Vukojevic. Mr Ninkovic was described by as the leader of a Serbian drug cartel and Mr Vukojevic a former policeman-turned-criminal.
"Both suspects attempted to resist arrest and to escape, but special police teams apprehended them," the officials said.
Mr Zoran Zivkovic, a former Djindjic ally nominated to succeed him as prime minister, later told Serbia's parliament that "a large quantity of arms and explosives" have been seized during 750 arrests.
Mr Zivkovic said organised criminals with links both to former President Slobodan Milosevic and "current political and financial structures" were responsible for Mr Djindjic's death but did not elaborate.
Earlier the government said investigators found a quantity of weapons in a specially concealed concrete bunker in a raid on the home of murdered underworld don, Zeljko Raznatovic, nicknamed Arkan.
His widow was arrested for sheltering key suspects sought in Mr Djindjic's killing.
AP
