An improved system and method is provided for identifying web communities from seed sets of web pages. A seed set of web pages may be represented as a set of seed vertices of a graph representing a collection of web pages. An initial probability distribution may be constructed on vertices of the graph by assigning a nonzero value to the vertices belonging to the seed set. Then a sequence of probability distributions may be produced on the vertices of the graph by modifying the probability distribution over a series of one-step walks of the probability distribution over the vertices of the graph. For each probability distribution produced in the sequence, level sets of vertices may be generated, and a level set with minimal conductance may be selected for each probability distribution. The level set with the least conductance may then be output representing a community of web pages.