MADRID, Spain -- Spanish National Police arrested four suspected jihadis Saturday in the country's North African enclave of Ceuta who allegedly had formed a terror cell and were ready to carry out an attack, the Interior Ministry said.

Interior Minister Jorge Fernandez Diaz said investigators, working with their Moroccan counterparts, were struck by the similarities between the suspected cell members and the two French brothers who killed 12 people in an attack upon the Charlie Hebdo newspaper in Paris.

"These are two pairs of very radicalized brothers who are highly trained militarily, physically and mentally and are prepared to carry out an attack, and ready, according to the police, to blow themselves up in the act," Fernandez Diaz said.

Two houses in Ceuta were searched in Saturday morning police raids and four men, all Spanish citizens of Moroccan origin, were arrested, the agency said. Officers found an automatic pistol, ammunition, military fatigues, face-concealing hoods, Spanish vehicle license plates, large machetes, knives and documents.

The ministry said the four were following instructions given by the ISIS leader, Abu Bakr al-Baghdadi, via what it called "a powerful and aggressive communication campaign" including jihadi Internet forums and websites.

Investigators were still assessing the cell's "infrastructure to carry out terror attacks in the country," the ministry said.

Spain and Morocco have arrested dozens of suspected jihadist militants and recruiters in recent years, especially around Melilla and Ceuta, Spanish coastal cities in North Africa that are surrounded by Morocco.