Prime Minister António Costa of Portugal said yesterday in a televised address he had resigned to the President of the Republic Marcelo Rebelo de Sousa.

Costa said the role of the prime minister was incongruous with suspicion of its involvement in a criminal act.

The resignation came hours after the public learned that police officers had searched Costa’s office as part of an investigation into alleged corruption involving hydrogen and lithium projects. Police also searched the homes of the Minister of Climate Action, Duarte Cordeiro, and Minister of Infrastructure, João Pedro Matos Fernándey.

Costa asserted his innocence in the criminal case in the address.

The Prosecutor General’s Office (PGO) released a statement yesterday confirming that 145 police officers, 20 magistrates, and nine Tax and Customs Authority officials had searched 17 homes, five lawyers’ offices, and 20 non-homes as part of a criminal investigation into malfeasance, corruption, and influence peddling.

Facts about the case, according to the statement, include lithium exploration concessions awarded to Romano, Montalegre, and Borroso, Boticas, mines; and a project related to a hydrogen energy production facility in Sines.

The PGO said it had issued warrants for the arrest of the prime minister's chief of staff, Vitor Escaria, and the mayor of Sines, Nuno Mascarenhas, among others.