LISBON, Portugal — Portugal’s defense minister says the army national armory where hand grenades, ammunition and other weapons were stolen last month was vulnerable due to its “obsolete” electronic surveillance system.

Defense Minister Jose Azeredo Lopes says ordnance still stored there will be moved to arsenals kept by the Navy and the Air Force, which meet NATO standards.

Azeredo Lopes says senior military officials warned the government last September that army installations were in a state of disrepair but intelligence services classified security risks as low. He told public broadcaster RTP on Wednesday night that military spending priorities were poorly defined. He refused to any link between the June 28 break-in and cuts in defense spending.

The public prosecutor is investigating the theft, assisted by police, military investigators and the National Counter-Terrorism Unit.