US bunker bombs on Yemen put Iran, China and N Korea on notice

In a high-stakes show of force, the US has dropped bunker-buster bombs on underground weapons depots in Yemen, the latest sign that the Gaza war is spreading across the wider region.

This month, multiple media outlets reported that the US deployed B-2 Spirit stealth bombers to strike underground weapons storage facilities controlled by Yemen’s Iran-backed Houthi rebels, marking the US’s first use of the bomber in the region.

The B-2s reportedly dropped GBU-57 Massive Ordnance Penetrator (MOP)/B bunker-buster bombs on five bunkers housing weapons used in attacks on vessels in the Red Sea.

US Defense Secretary Lloyd Austin described the strike as a demonstration of the US’s ability to target deeply buried and fortified sites, emphasizing that it was authorized by US President Joe Biden to degrade the Houthis’ capability.

The Houthis, who have attacked over 80 vessels since October 2023, have intensified their missile and drone strikes in response to the Gaza conflict, including actions against Israeli and US assets.

The strike also served as an indirect warning to Iran, a key Houthi ally, given its ongoing tensions with Israel and the US. Despite the sophisticated nature of the operation, no immediate civilian casualties were reported.

While details about the GBU-57 MOP/B remain classified, Global Security mentions that the munition is a powerful, precision-guided bomb weighing nearly 13,600 kilograms and containing over 2,400 kilograms of explosives that is designed to penetrate deeply buried targets.

Global Security says GPS-aided Inertial Navigation System (INS) guides the bomb, which can be deployed from B-52 and B-2 bombers and can breach 61 meters of 34.5 megapascal (MPa) reinforced concrete or 38 meters of