The Twitter homepage appears on a screen in Washington on September 2010. Twitter on Friday said it cut celebrity-tracking service JustSpotted off from a pipeline of "tweets" that could be tapped to map the whereabouts of stars.

Twitter on Friday said it cut celebrity-tracking service JustSpotted off from a pipeline of "tweets" that could be tapped to map the whereabouts of stars.

JustSpotted will launch Tuesday with an online map that pinpoints celebrity sightings in real time using updates from sources including , , and location-based check-in service FourSquare.

JustSpotted is a reincarnation of real-time Scoopler, which had licensed a "fire hose" data feed of all public from Twitter.

"JustSpotted.com is not the product we licensed, and we have terminated their agreement," a Twitter spokesman said in response to an AFP inquiry.

Twitter had nothing to do with the development of JustSpotted, the spokesman stressed.

The JustSpotted homepage on Friday featured a world atlas with icons marking locations where people reported sightings of famous folks ranging from movie stars to US President Barack Obama and the Dalai Lama.

A message on the page promised the service would launch in four days.

"JustSpotted shows you what your favorite celebrity is up to right now and where they were last spotted," said service founder and chief executive AJ Asver.

The service promised to deliver "a real-time feed of every celebrity's activity."

Key features listed by JustSpotted included technology that sifted public Twitter comments for celebrity sightings and comments about what they were doing.

While branded by some as a potential resource for stalkers, JustSpotted billed itself as "celebrity friendly" and said stars can make deals to use the service to promote their images or messages.