Detention and seizure of goods: GST penalty and release framework requires notice, payment, or security for release. Detention and seizure under GST permit authorities to detain or seize goods or conveyances transported or stored in contravention of the law only after serving an order; detained goods may be released on payment of prescribed penalties or on furnishing equivalent security. Penalty rates differ for taxable and exempt goods and depend on whether the owner or transporter pays; a transporter can secure conveyance release by paying the lesser of a statutory cap or the determined penalty. The proper officer must issue a notice and pass an order within specified seven day timelines, and goods not secured by payment within fifteen days may be sold or disposed, with a shortened period for perishable or hazardous items.