GST offences punishment: illicit supplies, false invoices and fraudulent credits attract imprisonment and fines, with cognizability limits. Specified GST offences include supplying without invoice, issuing invoices without supply leading to wrongful input tax credit or refund, availing input tax credit on such invoices, failing to remit collected tax beyond three months, evading tax, falsifying records, obstructing officers, dealing in goods or services known to be liable to confiscation, destroying evidence, and supplying false information; penalties are tiered by amount of tax evaded or credit/refund wrongly taken, with higher tiers attracting longer imprisonment and fine, repeat convictions increasing punishment, certain imprisonment terms subject to a statutory minimum, specified invoice-related high-value offences being cognizable and non-bailable, and prosecution requiring prior sanction of the Chief Commissioner.