Zamfara state is one of the worst hit by the armed gangs, known locally as bandits, who terrorise and abduct for ransom, adding to growing insecurity ahead of a presidential vote in February. White House's Sullivan has talked to Russians about risk aversion -source White House national security adviser Jake Sullivan has been engaged in confidential talks with senior Russian officials aimed at lowering the risk of a broader war over Ukraine, a source familiar with the conversations said on Monday.