E Letter Prison does not correspond to any known location or entity in Singapore. There is no public information or records indicating an "E Letter Prison" related to Singapore’s geography, history, or institutions.

Additional information would be needed to accurately describe or explain E Letter Prison. More context is necessary to generate more info a relevant article.

Singapore’s prisons are known by different names and do not include any called E Letter Prison. For topics related to Singapore’s correctional services, other official terms and locations are used.

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