NEW DELHI — In a set of telephone transcripts and recordings that were published by an Indian website this month, high-ranking intelligence and security officers from the western state of Gujarat can be heard reporting back on an unusual assignment: covertly tracing every movement of a young woman, meticulously documenting her contacts with men. Their findings were passed to another high-ranking official they referred to as “Saheb.”

Though no one mentions his name in the transcripts, the context leaves little doubt that Saheb is Narendra Modi, Gujarat’s chief minister, who hopes to be India’s next prime minister.

The “snooping controversy,” as it has been called by Indian newspapers, comes six months before national elections, as Mr. Modi’s Bharatiya Janata Party rides a wave of anti-incumbency sentiment. After a flurry of reports in the Indian news media, Mr. Modi’s government on Monday appointed a two-member commission to investigate charges that surveillance of the young woman had been carried out illegally.

After the transcripts were published, a spokeswoman for Mr. Modi’s party acknowledged that Mr. Modi had used government resources to monitor “the girl,” but did so because her father had requested security for her, so it was not a violation of her rights. Another version has come from a suspended civil servant from Gujarat, who says he fell out with Mr. Modi because he had information about a secret relationship between the leader and the young woman, an architect. The woman, who has since married, has made no public statements.