Centre that issues timely tsunami information messages. The messages can be information, watch, or warning messages, and are based on the available seismological and sea level data as evaluated by the TWC, or on evaluations received by the TWC from other monitoring agencies. The messages are advisory to the official designated emergency response agencies. Regional TWC monitor and provide tsunami information to Member States on potential ocean-wide tsunamis using global data networks, and can often issue messages within 20 minutes of the earthquake. Local TWC monitor and provide tsunami information on potential local tsunamis that will strike within minutes. Local TWC must have access to continuous, real-time, densely-spaced data networks in order to characterize the earthquakes within seconds and issue a warning within minutes. An example of a Regional Tsunami Warning Centre is the Pacific Tsunami Warning Center which provides international tsunami warnings to the Pacific. After the 26th December 2004 tsunami, the PTWC and JMA have been acting as an Interim Regional TWC for the Indian Ocean. Examples of sub-regional TWC are the NWPTAC operated by the Japan JMA, WC/ATWC operated by the USA NOAA NWS, and CPPT operated by France. These centres, along with Russia and Chile, also act as national TWC providing local tsunami warnings for their countries.