Vice President Mike Pence used a private email account to conduct public business when he was governor of Indiana, a practice that was legal but raised questions about the security of the communications, some of which addressed sensitive topics.

Mr. Pence used an AOL email account to communicate with top advisers on matters including the security gates at the governor’s residence and the state’s response to terrorist attacks across the globe, The Indianapolis Star reported Thursday night.

Mr. Pence’s use of personal email to conduct public business echoed Hillary Clinton’s use of a private server and email account when she was secretary of state. That practice was the subject of investigations, drew considerable criticism from Republicans and was frequently used as fodder by President Trump during his campaign.

In an appearance on “Meet the Press” in September, Mr. Pence, who took office as governor in 2013, said Mrs. Clinton had used the private server to keep her emails “out of the public reach, out of public accountability.”