Spanish police were investigating Thursday a series of letter bombs sent to targets including the prime minister and the US embassy, similar to one which went off at the Ukrainian embassy, hurting a staff member. The interior ministry revealed that an envelope with “pyrotechnic material” had arrived at Prime Minister Pedro Sanchez’s official residence on November 24. It was destroyed in a controlled explosion. Spain’s High court meanwhile announced it had broadened an initial investigation over the Ukraine embassy letter bomb to cover the all the other incidents. Both announcements came a day after the security officer at Ukraine’s embassy in Madrid suffered a light injury to one hand while opening a letter bomb addressed to the Ukrainian ambassador, an incident that prompted Kyiv to boost security at its embassies worldwide. That letter, like the others discovered, arrived by regular mail. Later in the evening, a second “suspicious postal shipment” was intercepted at the headquarters of military equipment firm Instalaza in the northeastern city of Zaragoza, the interior ministry said. Instalaza makes the grenade launchers that Spain donates to Ukraine. Then on Thursday morning letter bombs arrived and at the defence ministry; and at an air base in Torrejon de Ardoz, just outside Madrid, from where weapons donated by Spain are sent to Ukraine. “The characteristics of the envelopes, as well as their content, are similar in the five cases,” Spain’s Secretary of State of Security, Rafael Perez, told journalists.