Nine other people were injured. Russian news agencies reported several of Aliev's bodyguards were among those injured, as well as four of the suspected attackers. Previous reports had said the attackers had been detained.
Aliev was wounded in a similar attack last September.
Police and local officials have been targeted in a number of attacks in Daghestan recently. Officials have blamed some of the violence on Chechen-linked militants, and some on local criminal gangs.