GUWAHATI, Jan 24 ? Even as the city police continued its city-wide raid and search operations in the run-up to the Republic Day celebrations on Sunday, it achieved a major success this evening by unearthing 55 rounds of assorted ammunition from the campus of the Assam State Zoo. Police sources said that a tip off was received about suspected ULFA cadres trying to conceal some arms and ammunition in the zoo campus. Based on that, a police team, led by DSP Nanda Singh, discovered the bullets buried in the ground in the eastern corner of the zoo. The booty included 26 rounds of AK-47 ammunition, 27.9 mm bullets and two cartridges of US carbine.