The move by WHDH has prompted a threat from NBC to strip the TV station of its network affiliation.
Leno is leaving "The Tonight Show" in June, and his new prime-time program on NBC is scheduled to begin in September.
Ed Ansin, who owns WHDH's parent company, told The Boston Globe he did not believe Leno's new show would be successful. He said the station would do better financially with a news show that competes with Fox-affiliated WFXT-TV's highly rated 10 p.m. newscast.
NBC TV Network president John Eck said in a statement that WHDH's move is a "flagrant violation" of its contract with the network.
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