Gary Sinise and Melina Kanakaredes star in CSI:NY

CSI: NY drew 19.3m viewers in its debut against the second of two Law and Order episodes, Nielsen Media Research said.

Law and Order, based around a veteran detective, had an audience of 18.9m in its first hour and 15.4m during CSI, which follows a forensic investigator.

CSI had the most 18-49 and 25-54-year-old viewers and the most in New York.

The 18-to-49-year-old group is used by most networks to gauge prime- time success because they are the target group for advertisers.

It's encouraging for network television that people seemed to be aware that new things were coming on Jeff De Rome NBC

The latest offering from producer Jerry Bruckheimer's CSI franchise marked a promising start for CBS in its bid to finally gain ground in the Wednesday 10 o'clock hour.

NBC has long dominated the slot with Law and Order.

But executives at the network said they were not surprised at Wednesday's numbers, given the hype surrounding the CSI franchise at the official start of the US autumn season this week.

NBC spokesman Jeff De Rome said the network was instead cheered by relatively high viewing levels on TV overall.

"It's encouraging for network television that people seemed to be aware that new things were coming on, and that people were checking things out," he said.

The original CSI: Crime Scene Investigation, entered its fifth season on Thursday night against NBC's The Apprentice.